Adamantinoma

Adamantinoma is a rare, low-grade malignant primary bone tumor with a striking predilection for the diaphysis and metaphysis of the tibia (occasionally the fibula, and rarely other long bones), accounting for less than 0.1-0.5% of all primary bone tumors. It is histologically biphasic, combining keratin- and p63-positive epithelial cell nests within an osteofibrous (fibro-osseous) stroma, and is named for its histological resemblance to ameloblastoma ("adamantinoma" of the jaw) despite arising in an unrelated anatomic site and lineage. WHO classification recognizes classic adamantinoma (with tubular, basaloid, spindle-cell, and squamoid growth patterns), the osteofibrous dysplasia-like (OFD-like) form, and a rare dedifferentiated form with high-grade sarcomatous transformation; these are curated here as histopathologic variants of a single entity rather than as subtypes, because the boundaries between them are diagnostically unstable and the relationship between osteofibrous dysplasia, OFD-like adamantinoma, and classic adamantinoma remains a genuinely unsettled histogenetic question (see `discussions`). Despite its low-grade designation, adamantinoma carries a substantial long-term risk of local recurrence (15-31% for classic adamantinoma, 22-43% for the OFD-like form) and pulmonary metastasis (10-27%, essentially confined to classic adamantinoma), with recurrences reported more than 15 years after initial treatment. Wide surgical resection with uncontaminated margins is the most consistently protective factor and the mainstay of treatment, as the tumor is largely resistant to conventional chemotherapy and radiotherapy.

Ask OpenScientist

Ask a research question about Adamantinoma. OpenScientist will conduct autonomous deep research using the Disorder Mechanisms Knowledge Base and PubMed literature (typically 10-30 minutes).

Submitting...

Do not include personal health information in your question. Questions and results are cached in your browser's local storage.

6
Pathophys.
4
Histopath.
8
Phenotypes
1
Gaps
11
Pathograph
3
Medical Actions
4
Differentials
1
Deep Research
?

Discussions and Knowledge Gaps

1
Does osteofibrous dysplasia progress through an OFD-like adamantinoma intermediate to classic adamantinoma along a single histogenetic continuum, or are these three diagnostically overlapping but biologically separate entities?
KNOWLEDGE GAP OPEN adam_ofd_progression_sequence
Shared cytogenetic findings (trisomies 7, 8, and 12 reported in both OFD and adamantinoma) and shared, if focal, p63/keratin epithelial positivity in OFD have long been read as evidence of a common histogenesis and a possible progression sequence from OFD through OFD-like adamantinoma to classic adamantinoma. However, a contemporary genomic comparison found classic adamantinomas carry multiple chromosome/arm-level copy-number gains that OFDs largely lack, arguing the two may be genetically distinct rather than points on one continuum; and the largest recent single-institution clinicopathologic series observed a morphological continuum among the three diagnoses but did not observe any OFD progressing to adamantinoma during prospective follow-up (median 51 months, range 4-98 months). Both the "shared histogenesis/progression" and "distinct entities" readings remain live in the literature, and no study to date has followed a cohort of confirmed OFD cases long enough, with sufficiently consistent molecular workup, to settle the question. This bears directly on clinical management: if OFD can progress to a malignant tumor, that argues for closer surveillance of pediatric OFD than is currently standard.
Proposed experiments
Prospective longitudinal molecular cohort of OFD, OFD-like adamantinoma, and classic adamantinoma
exp_adam_ofd_longitudinal_molecular_cohort
Assemble a multi-institutional cohort of histologically confirmed OFD cases with long-term (>15 year) clinical and radiographic follow-up, paired with serial genomic profiling (copy-number/SNP array or targeted sequencing) of the lesion at diagnosis and at any subsequent biopsy or recurrence, to determine whether any lesion acquires the classic-adamantinoma copy-number gain pattern over time and whether that acquisition precedes clinical/histologic progression.
Show evidence (4 references)
PMID:9242211 SUPPORT Human Clinical
"The trisomies 7, 8, and 12 also were described in OFD, which suggests a common histogenesis of OFD and adamantinoma."
Represents the "shared histogenesis/progression" position in the literature.
PMID:12679847 SUPPORT Other
"Cytokeratin subset immunohistochemical stains and cytogenetic studies performed in recent years suggest a common histogenesis for these three entities."
Independent review reinforcing the "shared histogenesis/progression" position across OFD, OFD-like adamantinoma, and classic adamantinoma.
PMID:42379271 SUPPORT Human Clinical
"In conclusion, classic adamantinomas and OFD might be genetically distinct. Classic adamantinomas harbored multiple alterations, including chromosome/arm-level copy number gains, the detection of which could aid their distinction from OFDs."
Represents the more recent, genomically-based "distinct entities" position, in tension with the earlier common-histogenesis reading.
+ 1 more reference

Pathophysiology

6
Biphasic Epithelial-Osteofibrous Neoplastic Proliferation
Adamantinoma is defined by a neoplastic proliferation of keratin- and p63-positive epithelial cells, arranged in tubular, basaloid, spindle-cell, or squamoid patterns, embedded within a fibro-osseous (osteofibrous) stroma. The epithelial component shows a keratin subclass immunoreactivity pattern (widespread keratin 14 and 19, with keratin 5 in the majority of cases) that is independent of histologic growth pattern and is conserved in local recurrences and metastases, supporting a common basal epithelial cell-like histogenesis for all growth patterns. Almost all tumors arise in the tibial diaphysis or metaphysis.
basal epithelial-like tumor cell CL:0000646 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves basal epithelial-like tumor cell, annotated with basal cell (CL:0000646). CL:0000646 is a cell type from the Cell Ontology. osteofibrous stromal fibroblast CL:0000057 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves osteofibrous stromal fibroblast, annotated with fibroblast (CL:0000057). CL:0000057 is a cell type from the Cell Ontology.
aberrant basal epithelial differentiation of tumor cells GO:0030855 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves abnormal aberrant basal epithelial differentiation of tumor cells, annotated with epithelial cell differentiation (GO:0030855). GO:0030855 is a biological process from the Gene Ontology. ⚠ ABNORMAL
tibial diaphysis UBERON:0013280 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in tibial diaphysis, annotated with diaphysis of tibia (UBERON:0013280). UBERON:0013280 is an anatomical location from the Uberon multi-species anatomy ontology.
Show evidence (2 references)
PMID:7694513 SUPPORT Human Clinical
"The results revealed the widespread presence of keratins 14 and 19 in all specimens studied; 74% showed immunoreactivity of keratin 5"
Establishes the conserved keratin immunoprofile of the epithelial component across adamantinoma growth patterns and recurrences.
PMID:7694513 SUPPORT Human Clinical
"Our results suggest a basal epithelial cell-like differentiation of adamantinomas."
Directly supports the basal epithelial-like histogenesis claim.
Recurrent Chromosomal Copy-Number Gains Without an Established Driver
Cytogenetic and, more recently, genomic studies of classic adamantinoma recurrently identify extra copies of chromosomes 7, 8, 12, 19, and 21 (and, in a targeted sequencing/SNP-array series, chromosomes 7, 8, 10, 12, and/or 19), sometimes accompanied by isolated structural events (e.g., a chromosome 12q tandem duplication, an FGFR1 rearrangement, or an NRAS p.G12D variant in single cases). No single recurrent driver gene, mutation, or fusion has been established across cases: this genomic profile is what most clearly distinguishes true adamantinoma from its principal molecular mimic, "adamantinoma-like Ewing sarcoma," which instead carries the canonical EWSR1::FLI1/ERG t(11;22) or t(21;22) translocations that are consistently absent from true adamantinoma. Osteofibrous dysplasia-like adamantinoma is genomically heterogeneous and, in a small paired series, could show either no detectable variants or the same chromosome 7/8/19 gain pattern as classic adamantinoma, so genomic profiling has been proposed as an aid to (but not yet a settled arbiter of) distinguishing these entities.
Show evidence (4 references)
PMID:11227067 SUPPORT Human Clinical
"Cytogenetic or molecular cytogenetic analysis of four adamantinomas, and a review of eleven cases in the literature reveals extra copies of chromosomes 7, 8, 12, 19, and 21 as recurrent in this neoplasm."
Establishes the recurrent whole-chromosome copy-number gain pattern.
PMID:9242211 SUPPORT Human Clinical
"Two of them revealed trisomies 7, 8, 12, and 19, combined with a balanced translocation, t(10;12), with centromere breakpoints in one tumor."
Independent cytogenetic series confirming the recurrent trisomy pattern and demonstrating additional structural heterogeneity between cases (no single lesion is shared by all tumors).
PMID:42379271 SUPPORT Human Clinical
"The 3 classic adamantinomas harbored multiple copy number gains involving chromosome 7, 8, 10, 12, and/or 19. Focal deletion of chromosome 17, intergenic rearrangement involving FGFR1, and NRAS p.G12D were each present in 1 classic adamantinoma."
Contemporary NGS/SNP-array/Hi-C study confirming the copy-number gain pattern and showing that isolated structural/point variants differ from tumor to tumor rather than converging on one driver.
+ 1 more reference
Local Cortical Bone Destruction and Structural Compromise
Progressive intracortical and intramedullary tumor growth within the tibial diaphysis destroys and thins cortical bone, producing anterior tibial bowing, a palpable mass, bone pain, and, in advanced or long-standing disease, structural weakening predisposing to pathologic fracture.
tibial diaphysis UBERON:0013280 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in tibial diaphysis, annotated with diaphysis of tibia (UBERON:0013280). UBERON:0013280 is an anatomical location from the Uberon multi-species anatomy ontology.
Show evidence (1 reference)
PMID:30844202 SUPPORT Human Clinical
"Adamantinomas are rare, low-grade malignant bone tumors of uncertain histogenesis that predominately affect the diaphyses and metaphyses of the tibia."
Establishes the anatomic site of the destructive tumor process.
Local Recurrence After Incomplete Surgical Resection
Local recurrence is common and can occur late (documented beyond 15 years post-treatment). Across a synthesized literature base, local recurrence rates range from 15-31% for classic adamantinoma and 22-43% for the OFD-like variant. Wide resection with uncontaminated margins is the most consistently protective surgical variable identified across the case-series literature; intralesional or marginal margins predispose to recurrence.
Show evidence (4 references)
PMID:42496518 SUPPORT Human Clinical
"Local recurrence rates for classic adamantinoma (AD) range from 15% to 31%, with metastatic rates from 10% to 27%, predominantly to the lung."
Quantifies the recurrence and metastasis rates from a synthesis of the case-series literature.
PMID:42496518 SUPPORT Human Clinical
"Wide resection with uncontaminated margins is the most consistently protective surgical variable (hazard ratio 0.164; p < 0.001)."
Quantifies the protective effect of margin status on outcome.
PMID:42496518 SUPPORT Human Clinical
"Late recurrences beyond 15 years are documented in multiple series, supporting prolonged surveillance."
Documents the long natural history requiring lifelong surveillance.
+ 1 more reference
Hematogenous and Lymphatic Metastasis
Classic adamantinoma metastasizes predominantly to the lungs, in an estimated 10-27% of cases, but metastatic spread is not confined to the lung: it is also reported to regional lymph nodes (including a case with inguinal nodal recurrence and no pulmonary disease at all) and, less commonly, to abdominal/pelvic sites, liver, brain, and skeleton. In contrast, the OFD-like variant, despite a locally aggressive recurrence rate, shows no metastases in series that report it separately, indicating a biologically distinct clinical behavior from classic adamantinoma despite their morphologic overlap.
lung UBERON:0002048 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in lung (UBERON:0002048). UBERON:0002048 is an anatomical location from the Uberon multi-species anatomy ontology. lymph node UBERON:0000029 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in lymph node (UBERON:0000029). UBERON:0000029 is an anatomical location from the Uberon multi-species anatomy ontology.
Show evidence (5 references)
PMID:42496518 SUPPORT Human Clinical
"The osteofibrous dysplasia-like subtype (OFD-AD) showed no metastases in any series that reports this subtype separately but carries a locally aggressive recurrence rate of 22-43%."
Directly supports the biological distinction between classic adamantinoma metastatic potential and the OFD-like variant's purely local aggressiveness.
PMID:42496518 SUPPORT Human Clinical
"Because metastatic spread is not confined to the lung, chest CT alone may be insufficient for surveillance in selected high-risk patients, in whom staging beyond the chest should be considered"
Directly supports that metastatic spread extends beyond the lung alone, motivating the broader nodal/abdominal-pelvic framing of this node rather than a pulmonary-only model.
PMID:41653544 SUPPORT Human Clinical
"Five out of 28 (17.9%) patients with an adamantinoma developed recurrences and 5 (17.9) developed metastases."
Independent single-institution series quantifying metastatic frequency among classic adamantinomas.
+ 2 more references
Sarcomatoid Dedifferentiation with Loss of Epithelial Phenotype
Rarely, classic adamantinoma undergoes high-grade sarcomatoid transformation, with progressive loss of pankeratin and other epithelial marker expression in the transformed component (a "revertant mesenchymal phenotype"). This dedifferentiated form behaves more aggressively; the evidence base for its mechanism is limited to a small number of case reports.
Show evidence (1 reference)
PMID:20717000 SUPPORT Human Clinical
"On the en bloc resection specimen, areas of classic adamantinoma were found but most of the tumor corresponded to a high-grade neoplasm with 2 histologic patterns: one made up by epithelial nests with a basaloid arrangement and positive for pankeratins and so-called glandular keratins, and a..."
Direct description of a dedifferentiated adamantinoma with sarcomatoid loss of the epithelial immunophenotype.

Histopathology

4
Keratin/p63-Positive Epithelial Immunoprofile VERY_FREQUENT
The neoplastic epithelial nests express pankeratin (AE1/AE3) in approximately 95% of cases, with p40 and p63 also positive in the large majority of cases; this keratin/p63 epithelial immunoprofile within an otherwise osteofibrous bone lesion is the diagnostic anchor that establishes an epithelial (rather than purely mesenchymal or fibro-osseous) neoplasm.
Show evidence (2 references)
PMID:41653544 SUPPORT Human Clinical
"Pan keratin (AE1/AE3) was positive in 18/19 (94.7%) OFDs and 19/20 (95%) adamantinomas. P40 (5/5, 100%) and p63 (6/8, 75%) were useful in the diagnosis of adamantinoma."
Direct quantification of pankeratin/p40/p63 positivity rates.
PMID:21674157 SUPPORT Human Clinical
"The epithelial component in adamantinoma was found to stain for p63."
Establishes p63 as a marker of the epithelial tumor component.
Tubular/Basaloid/Spindle-Cell/Squamoid Growth Patterns (Classic Adamantinoma)
Classic adamantinoma displays a spectrum of architectural growth patterns — tubular, basaloid, spindle-cell, and squamoid — within the same underlying epithelial-osteofibrous biphasic lesion. The keratin immunoreactivity pattern is conserved across all of these patterns, indicating a shared histogenesis; spindle and basaloid patterns are disproportionately associated with recurrence and metastasis.
Show evidence (2 references)
PMID:7694513 SUPPORT Human Clinical
"This keratin immunoreactivity pattern was independent of histologic subtype, despite marked variety in differentiation pattern, suggesting a common histogenesis for all subtypes of adamantinoma."
Directly supports that the growth-pattern variants share a common histogenesis rather than being distinct entities.
PMID:41653544 SUPPORT Human Clinical
"The most commonly associated patterns with recurrences and metastasis in a classic adamantinoma were spindle and basaloid."
Links specific growth patterns to prognostic behavior.
Osteofibrous Dysplasia-Like Pattern
A fibro-osseous pattern resembling osteofibrous dysplasia, with only scattered or focal keratin/p40-positive epithelial cell clusters (sometimes detectable only by immunostain, not on light microscopy). Distinguishing an OFD-like adamantinoma from osteofibrous dysplasia proper, and from classic adamantinoma, is a recognized source of interobserver diagnostic disagreement (see `discussions`).
Show evidence (2 references)
PMID:42379271 SUPPORT Human Clinical
"one case with tumor clusters visible only on cytokeratin immunostain harbored no variants, whereas another case with tumor clusters visible on light microscopy and cytokeratin/p40 immunostains showed gains of chromosome 7, 8, 19, and 20"
Documents the diagnostically ambiguous, immunostain-dependent nature of the OFD-like epithelial component.
PMID:41653544 SUPPORT Human Clinical
"After a review, the diagnosis was modified in 12/58 (20.7%) tumors; with 4 OFDs revised to FDs; 2 FDs to OFDs; 2 intra-osseous SSs to classic adamantinomas; 3 OFD-like adamantinomas to classic adamantinomas, and a single de-differentiated adamantinoma to classic adamantinoma."
Quantifies the substantial rate of diagnostic revision among OFD, OFD-like adamantinoma, and classic adamantinoma on expert review, supporting that these categories are diagnostically unstable rather than sharply demarcated entities.
Sarcomatoid Dedifferentiation VERY_RARE
A rare high-grade component with loss of epithelial (keratin) marker expression arising within or after classic adamantinoma, sometimes with a completely "revertant" mesenchymal/sarcomatoid phenotype on recurrence.
Show evidence (1 reference)
PMID:20717000 SUPPORT Human Clinical
"Three cases of adamantinomas with sarcomatoid transformation of the epithelial component have been described but the tumours still preserved an epithelial immunophenotype."
Establishes the rarity and prior documentation of dedifferentiation in adamantinoma.

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.
Pathograph: causal mechanism network for Adamantinoma Interactive directed graph showing how pathophysiology mechanisms, phenotypes, genetic factors and variants, experimental models, environmental triggers, and treatments relate through causal and linked edges.

Phenotypes

8
Limbs 1
Tibial Bowing HP:0002982 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Tibial bowing (HP:0002982). HP:0002982 is a phenotype from the Human Phenotype Ontology.
Show evidence (2 references)
PMID:35094574 SUPPORT Human Clinical
"41 lesions (40.6%) presented with radiological deformity (> 10°): apex anterior in 97.6%."
Directly quantifies anterior angular tibial deformity (bowing) in a 101-lesion tibial OFD case series, the benign end of the OFD/adamantinoma spectrum this phenotype describes.
PMID:38539216 SUPPORT Human Clinical
"OFD can present with asymptomatic, mass, pain, swelling, deformity (anterior bowing of the tibia), and even pathological fracture"
Independent narrative review confirming anterior tibial bowing (deformity) as a recognized clinical presentation across the OFD/adamantinoma spectrum.
Musculoskeletal 2
Pathologic Fracture HP:0002756 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Pathologic fracture (HP:0002756). HP:0002756 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:42496518 SUPPORT Human Clinical
"Pathological fracture at presentation was recorded in 10% to 21% across series"
Quantifies pathologic fracture frequency at presentation.
Osteolytic Bone Lesion Osteolysis HP:0002797 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Osteolytic soap-bubble lesion of the tibia, annotated with Osteolysis (HP:0002797). HP:0002797 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:34697136 SUPPORT Human Clinical
"In X-ray, it is usually seen as an eccentric and sometimes central, lobular, lytic lesion with sclerotic margins of overlapping radiolucency, and a characteristic 'soap-bubble' appearance."
Direct description of the characteristic osteolytic radiographic appearance.
Constitutional 1
Bone Pain HP:0002653 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Bone pain (HP:0002653). HP:0002653 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:39555331 SUPPORT Human Clinical
"patients typically present with a painful, swollen mass which can be palpated."
Direct support for pain as a common presenting feature.
Neoplasm 1
Pulmonary Metastasis Neoplasm of the lung HP:0100526 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Pulmonary metastasis of adamantinoma, annotated with Neoplasm of the lung (HP:0100526). HP:0100526 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:42496518 SUPPORT Human Clinical
"Local recurrence rates for classic adamantinoma (AD) range from 15% to 31%, with metastatic rates from 10% to 27%, predominantly to the lung."
Direct support for lung as the predominant metastatic site.
Other 3
Localized Extremity Mass Localized soft-tissue swelling on extremity HP:6000840 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Localized soft-tissue mass of the leg, annotated with Localized soft-tissue swelling on extremity (HP:6000840). HP:6000840 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:39555331 SUPPORT Human Clinical
"patients typically present with a painful, swollen mass which can be palpated."
Direct support for a palpable mass as a common presenting feature.
Bone Neoplasm Neoplasm of the skeletal system HP:0010622 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Adamantinoma of bone, annotated with Neoplasm of the skeletal system (HP:0010622). HP:0010622 is a phenotype from the Human Phenotype Ontology.
Nodal Metastasis Abnormal lymph node morphology HP:0002733 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Lymph node metastasis of adamantinoma, annotated with Abnormal lymph node morphology (HP:0002733). HP:0002733 is a phenotype from the Human Phenotype Ontology.
Show evidence (2 references)
PMID:39555331 SUPPORT Human Clinical
"metastasis occurs at rates as high as 18–32% primarily to lymph nodes or lungs"
Directly establishes lymph nodes as a primary metastatic site.
PMID:38486378 SUPPORT Human Clinical
"a positive emission tomography scan revealed mildly increased tracer uptake near the area of the previous lesion and in the right inguinal lymph node. Biopsies of the lesion and inguinal lymph node confirmed recurrence of the adamantinoma"
Case-level confirmation of inguinal lymph node metastatic recurrence.
💊

Medical Actions

3
Wide En Bloc Surgical Resection
Action: en bloc surgical resectionNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is en bloc surgical resection, annotated with En Bloc Resection (NCIT:C139567). NCIT:C139567 is a clinical intervention from the NCI Thesaurus. Ontology label: En Bloc Resection NCIT:C139567
Complete surgical excision with uncontaminated (wide) margins is the standard, and most consistently effective, treatment for adamantinoma. Conventional chemotherapy and radiotherapy have not been shown to be reliably effective, so margin-negative surgery is the primary curative-intent modality; reconstruction (e.g., with a vascularized fibular graft) is frequently required for the resulting tibial defect.
Show evidence (1 reference)
PMID:42496518 SUPPORT Human Clinical
"Wide resection with uncontaminated margins is the most consistently protective surgical variable (hazard ratio 0.164; p < 0.001)."
Quantifies the protective effect of wide-margin resection on recurrence risk.
Limb-Sparing Reconstruction
Action: limb salvage procedureNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is limb salvage procedure (NCIT:C16042). NCIT:C16042 is a clinical intervention from the NCI Thesaurus. Ontology label: Limb Salvage Procedure NCIT:C16042
Following wide resection of the tibial defect, limb-sparing reconstructive techniques (including vascularized or non-vascularized fibular grafts) are used to preserve limb function and avoid amputation where feasible.
Pazopanib (Limited Efficacy in Recurrent/Metastatic Disease)
Action: PharmacotherapyNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is Pharmacotherapy (NCIT:C15986). NCIT:C15986 is a clinical intervention from the NCI Thesaurus. NCIT:C15986
Agent: pazopanib CHEBI:71219 Chemical Entities of Biological Interest (CHEBI) Relation: this treatment uses this therapeutic agent This treatment uses pazopanib (CHEBI:71219). CHEBI:71219 is a therapeutic agent from Chemical Entities of Biological Interest.
The multi-target tyrosine kinase inhibitor pazopanib has been used in recurrent/metastatic adamantinoma when surgery alone is no longer curative, but case-level experience to date indicates limited standalone efficacy; adamantinoma has no consensus systemic-therapy guideline.
Show evidence (1 reference)
PMID:38486378 REFUTE Human Clinical
"This report showed that pazopanib as standalone treatment does not appear to have promising role on patient outcomes."
Case report directly reporting limited efficacy of pazopanib monotherapy for recurrent/metastatic adamantinoma.
🔬

Diagnosis

4
Plain Radiography (Soap-Bubble Osteolytic Lesion)
Initial imaging is plain radiography, which characteristically shows an eccentric, lobular, lytic lesion with sclerotic margins of overlapping radiolucency in the tibial diaphysis -- the classic "soap-bubble" appearance -- though the radiologic impression does not reliably predict the underlying histologic diagnosis (see the centrally-sampled-biopsy caveat below).
plain radiography of the affected bone NCIT:C38101 NCI Thesaurus (NCIT)
Show evidence (1 reference)
PMID:34697136 SUPPORT Human Clinical
"In X-ray, it is usually seen as an eccentric and sometimes central, lobular, lytic lesion with sclerotic margins of overlapping radiolucency, and a characteristic 'soap-bubble' appearance."
Direct description of the characteristic radiographic appearance.
Whole-Bone MRI for Multifocality and Skip Lesions
MRI of the entire involved bone is used both for differential diagnosis and to detect multifocal disease -- reported in approximately 24% of cases -- including a singular lobulated focus or several small nodules within multiple foci that may not be apparent on plain radiographs alone.
magnetic resonance imaging of the affected bone NCIT:C16809 NCI Thesaurus (NCIT)
Show evidence (3 references)
PMID:38486378 SUPPORT Human Clinical
"On magnetic resonance imaging (MRI), 2 morphological patterns have been described: a singular lobulated focus or several small nodules within multiple foci."
Directly describes the multifocal/skip-lesion MRI patterns relevant to whole-bone imaging.
PMID:42496518 SUPPORT Human Clinical
"Multifocality occurs in approximately 24% of cases"
Quantifies the frequency of multifocal disease that whole-bone MRI is intended to detect.
PMID:34697136 SUPPORT Human Clinical
"Magnetic resonance imaging seems to be the most appropriate examination for differential diagnosis between adamantinoma and other skeletal tumors."
Establishes MRI as the preferred differential-diagnosis imaging modality.
Chest CT for Metastatic Staging
Chest CT is used for pulmonary metastatic staging given the tumor's predilection for hematogenous lung spread, but chest CT alone can be insufficient in high-risk patients because metastatic spread is not confined to the lung (see `phenotypes#Nodal Metastasis`); staging beyond the chest should be considered in selected high-risk cases, and the optimal imaging modality, extent, and frequency of surveillance remain undefined.
computed tomography of the chest NCIT:C17204 NCI Thesaurus (NCIT)
Show evidence (1 reference)
PMID:42496518 SUPPORT Human Clinical
"Because metastatic spread is not confined to the lung, chest CT alone may be insufficient for surveillance in selected high-risk patients, in whom staging beyond the chest should be considered"
Directly supports both the chest-CT staging role and its limitation given non-pulmonary metastatic sites.
Centrally-Sampled Biopsy with Immunohistochemistry
Because the diagnostic epithelial component can be sparse and patchy -- especially in OFD-like adamantinoma, where it may be detectable only by immunostain and not on light microscopy (see `histopathology#Osteofibrous Dysplasia-Like Pattern`) -- adequate, ideally centrally-sampled biopsy with immunohistochemistry (pankeratin, p40, p63) is needed to avoid false-negative or misclassified diagnoses; radiologic-histologic concordance is imperfect even among experienced centers.
image-guided biopsy with immunohistochemistry NCIT:C15189 NCI Thesaurus (NCIT)
Show evidence (2 references)
PMID:18279517 SUPPORT Other
"To assure the histological diagnosis, pathologists should employ immunohistochemistry for demonstrating the sometimes sparse epithelial cell nests when the radiological features are suggestive of adamantinoma."
Directly states the sampling/immunohistochemistry caveat for the sparse epithelial component.
PMID:41653544 SUPPORT Human Clinical
"The radiological impression concurred with the histopathological diagnosis in 40% of OFDs and 60% of adamantinomas."
Quantifies imperfect radiologic-histologic concordance, motivating reliance on adequately sampled biopsy.
📊

Prevalence

1
United States (SEER Program, ICD-O-3 code 9261/3)
Cases In Literature Ultra Rare
74 patients identified in the SEER registry; median age at diagnosis 20-24 years.
Show evidence (1 reference)
PMID:39555331 SUPPORT Human Clinical
"Adamantinoma (AD) is a rare bone cancer accounting for less than 0.1-0.5% of all primary bone tumors."
SEER-based epidemiological analysis directly quantifying the population-level rarity of adamantinoma among primary bone tumors.
🔀

Differential Diagnoses

4

Conditions with similar clinical presentations that must be differentiated from Adamantinoma:

Overlapping Features Ameloblastoma is a locally aggressive odontogenic epithelial tumor of the jaw (mandible/maxilla) that shares keratin-positive epithelial histology with adamantinoma of long bone, and historically gave adamantinoma its name, but the two are anatomically, embryologically, and clinically distinct entities: ameloblastoma arises from odontogenic epithelium in the jaw, whereas adamantinoma is a primary bone tumor with a striking predilection for the tibial diaphysis and no odontogenic relationship. This entry (MONDO:0002422) is NOT ameloblastoma (MONDO:0017795).
Distinguishing Features
  • Arises in the jaw (mandible/maxilla) from odontogenic epithelium, not in long bones
  • No predilection for the tibial diaphysis
  • Distinct molecular drivers (e.g., BRAF V600E, SMO) not reported as recurrent in true adamantinoma
Show evidence (1 reference)
PMID:30844202 SUPPORT Other
"The tumor is called adamantinoma due to its histological similarity to ameloblastoma, often found in the mandible."
States the historical basis for the name shared with ameloblastoma while identifying the mandible as the site specific to ameloblastoma.
Overlapping Features Adamantinomatous craniopharyngioma is a WHO grade 1 epithelial neoplasm of the sellar/parasellar region arising from Rathke pouch epithelial remnants, driven by somatic CTNNB1 mutations. It shares only a descriptive histological label ("adamantinomatous," for its resemblance to ameloblastoma/adamantinoma-type epithelium) with the bone tumor curated in this entry; it is a completely separate disease, already curated in dismech as `Craniopharyngioma.yaml`, and is not a form of, subtype of, or related to skeletal adamantinoma (MONDO:0002422).
Distinguishing Features
  • Arises in the sellar/suprasellar region of the central nervous system, not in bone
  • Driven by somatic CTNNB1/Wnt pathway activation, not by the chromosomal copy-number gains seen in skeletal adamantinoma
  • Presents with visual, endocrine, and hypothalamic symptoms rather than a limb mass or bone pain
Adamantinoma-like Ewing Sarcoma
Overlapping Features A member of the Ewing sarcoma family of tumors that shows aberrant epithelial (cytokeratin) expression and, in some cases, an architectural resemblance to adamantinoma, but is genetically defined by the canonical Ewing sarcoma EWSR1::FLI1 t(11;22) or EWSR1::ERG t(21;22) translocation. These translocations are consistently absent in true adamantinoma, despite the misleading shared name.
Distinguishing Features
  • Carries the EWSR1::FLI1 t(11;22) or EWSR1::ERG t(21;22) translocation, absent in true adamantinoma
  • Not restricted to the tibial diaphysis in the same site-specific pattern as adamantinoma
  • Aggressive small round blue cell histology rather than the biphasic epithelial-osteofibrous pattern of adamantinoma
Show evidence (1 reference)
PMID:11592101 SUPPORT Human Clinical
"This study investigated the putative presence of t(11; 22) and t(21; 22) in 14 cases of adamantinoma by RT-PCR. These translocations were not found in any of these cases. The results support the view that these tumours are genetically and clinically distinct, but may eventually show overlapping..."
Directly establishes the genetic distinction between true adamantinoma and adamantinoma-like Ewing sarcoma despite morphologic overlap.
Osteofibrous Dysplasia Not Yet Curated MONDO:0011806
Overlapping Features A benign, self-limited fibro-osseous lesion of the tibial diaphysis in children, radiologically and histologically similar to OFD-like adamantinoma; distinguishing the two (and determining whether OFD can itself progress to adamantinoma) is an open diagnostic and histogenetic question (see `discussions`).
Distinguishing Features
  • Benign lesion, historically not considered to metastasize
  • Typically younger age at presentation (median 10 years vs 25 years for adamantinoma in one series)
  • Absent or only very focal/rare p63-positive epithelial cells on immunostain
Show evidence (1 reference)
PMID:41653544 SUPPORT Human Clinical
"The median age for OFD (10 years) was lower than that of adamantinoma (25 years)."
Quantifies the age-distribution distinction used to help separate the two entities clinically.
{ }

Source YAML

click to show
name: Adamantinoma
creation_date: "2026-08-26T23:27:22Z"
category: Cancer
categories:
- Bone Cancer
- Rare Cancer
- Low-Grade Malignant Neoplasm
synonyms:
- Adamantinoma of long bones
- Adamantinoma of the tibia
description: >-
  Adamantinoma is a rare, low-grade malignant primary bone tumor with a
  striking predilection for the diaphysis and metaphysis of the tibia
  (occasionally the fibula, and rarely other long bones), accounting for
  less than 0.1-0.5% of all primary bone tumors. It is histologically
  biphasic, combining keratin- and p63-positive epithelial cell nests
  within an osteofibrous (fibro-osseous) stroma, and is named for its
  histological resemblance to ameloblastoma ("adamantinoma" of the jaw)
  despite arising in an unrelated anatomic site and lineage. WHO
  classification recognizes classic adamantinoma (with tubular, basaloid,
  spindle-cell, and squamoid growth patterns), the osteofibrous
  dysplasia-like (OFD-like) form, and a rare dedifferentiated form with
  high-grade sarcomatous transformation; these are curated here as
  histopathologic variants of a single entity rather than as subtypes,
  because the boundaries between them are diagnostically unstable and the
  relationship between osteofibrous dysplasia, OFD-like adamantinoma, and
  classic adamantinoma remains a genuinely unsettled histogenetic question
  (see `discussions`). Despite its low-grade designation, adamantinoma
  carries a substantial long-term risk of local recurrence (15-31% for
  classic adamantinoma, 22-43% for the OFD-like form) and pulmonary
  metastasis (10-27%, essentially confined to classic adamantinoma), with
  recurrences reported more than 15 years after initial treatment. Wide
  surgical resection with uncontaminated margins is the most consistently
  protective factor and the mainstay of treatment, as the tumor is largely
  resistant to conventional chemotherapy and radiotherapy.
disease_term:
  preferred_term: adamantinoma
  term:
    id: MONDO:0002422
    label: adamantinoma
parents:
- Bone Cancer

prevalence:
- population: United States (SEER Program, ICD-O-3 code 9261/3)
  measure_type: CASES_IN_LITERATURE
  prevalence_class: ULTRA_RARE
  notes: >-
    74 patients identified in the SEER registry; median age at diagnosis
    20-24 years.
  evidence:
  - reference: PMID:39555331
    reference_title: "Adamantinoma: A SEER-based Epidemiological Analysis"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Adamantinoma (AD) is a rare bone cancer accounting for less than 0.1-0.5% of all primary bone tumors."
    explanation: >-
      SEER-based epidemiological analysis directly quantifying the
      population-level rarity of adamantinoma among primary bone tumors.

pathophysiology:
- name: Biphasic Epithelial-Osteofibrous Neoplastic Proliferation
  biological_scale: TISSUE
  description: >-
    Adamantinoma is defined by a neoplastic proliferation of keratin- and
    p63-positive epithelial cells, arranged in tubular, basaloid,
    spindle-cell, or squamoid patterns, embedded within a fibro-osseous
    (osteofibrous) stroma. The epithelial component shows a keratin
    subclass immunoreactivity pattern (widespread keratin 14 and 19, with
    keratin 5 in the majority of cases) that is independent of histologic
    growth pattern and is conserved in local recurrences and metastases,
    supporting a common basal epithelial cell-like histogenesis for all
    growth patterns. Almost all tumors arise in the tibial diaphysis or
    metaphysis.
  cell_types:
  - preferred_term: basal epithelial-like tumor cell
    term:
      id: CL:0000646
      label: basal cell
  - preferred_term: osteofibrous stromal fibroblast
    term:
      id: CL:0000057
      label: fibroblast
  locations:
  - preferred_term: tibial diaphysis
    term:
      id: UBERON:0013280
      label: diaphysis of tibia
  biological_processes:
  - preferred_term: aberrant basal epithelial differentiation of tumor cells
    modifier: ABNORMAL
    term:
      id: GO:0030855
      label: epithelial cell differentiation
  evidence:
  - reference: PMID:7694513
    reference_title: "Adamantinoma of the long bones: keratin subclass immunoreactivity pattern with reference to its histogenesis"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The results revealed the widespread presence of keratins 14 and 19
      in all specimens studied; 74% showed immunoreactivity of keratin 5
    explanation: >-
      Establishes the conserved keratin immunoprofile of the epithelial
      component across adamantinoma growth patterns and recurrences.
  - reference: PMID:7694513
    reference_title: "Adamantinoma of the long bones: keratin subclass immunoreactivity pattern with reference to its histogenesis"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Our results suggest a basal epithelial cell-like differentiation of adamantinomas."
    explanation: Directly supports the basal epithelial-like histogenesis claim.
  downstream:
  - target: Local Cortical Bone Destruction and Structural Compromise
    description: >-
      Intraosseous tumor growth destroys and remodels adjacent cortical
      bone in the tibial diaphysis.

- name: Recurrent Chromosomal Copy-Number Gains Without an Established Driver
  biological_scale: MOLECULAR
  mechanism_confidence: PROVISIONAL
  description: >-
    Cytogenetic and, more recently, genomic studies of classic adamantinoma
    recurrently identify extra copies of chromosomes 7, 8, 12, 19, and 21
    (and, in a targeted sequencing/SNP-array series, chromosomes 7, 8, 10,
    12, and/or 19), sometimes accompanied by isolated structural events
    (e.g., a chromosome 12q tandem duplication, an FGFR1 rearrangement, or
    an NRAS p.G12D variant in single cases). No single recurrent driver
    gene, mutation, or fusion has been established across cases: this
    genomic profile is what most clearly distinguishes true adamantinoma
    from its principal molecular mimic, "adamantinoma-like Ewing sarcoma,"
    which instead carries the canonical EWSR1::FLI1/ERG t(11;22) or t(21;22)
    translocations that are consistently absent from true adamantinoma.
    Osteofibrous dysplasia-like adamantinoma is genomically heterogeneous
    and, in a small paired series, could show either no detectable
    variants or the same chromosome 7/8/19 gain pattern as classic
    adamantinoma, so genomic profiling has been proposed as an aid to (but
    not yet a settled arbiter of) distinguishing these entities.
  evidence:
  - reference: PMID:11227067
    reference_title: "Extra copies of chromosomes 7, 8, 12, 19, and 21 are recurrent in adamantinoma"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Cytogenetic or molecular cytogenetic analysis of four adamantinomas,
      and a review of eleven cases in the literature reveals extra copies
      of chromosomes 7, 8, 12, 19, and 21 as recurrent in this neoplasm.
    explanation: Establishes the recurrent whole-chromosome copy-number gain pattern.
  - reference: PMID:9242211
    reference_title: "Cytogenetic analysis of adamantinoma of long bones: further indications for a common histogenesis with osteofibrous dysplasia"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Two of them revealed trisomies 7, 8, 12, and 19, combined with a
      balanced translocation, t(10;12), with centromere breakpoints in one
      tumor.
    explanation: >-
      Independent cytogenetic series confirming the recurrent trisomy
      pattern and demonstrating additional structural heterogeneity
      between cases (no single lesion is shared by all tumors).
  - reference: PMID:42379271
    reference_title: "Genomic Characterization of Classic Adamantinoma, Osteofibrous Dysplasia, and Osteofibrous Dysplasia-like Adamantinoma"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The 3 classic adamantinomas harbored multiple copy number gains
      involving chromosome 7, 8, 10, 12, and/or 19. Focal deletion of
      chromosome 17, intergenic rearrangement involving FGFR1, and NRAS
      p.G12D were each present in 1 classic adamantinoma.
    explanation: >-
      Contemporary NGS/SNP-array/Hi-C study confirming the copy-number
      gain pattern and showing that isolated structural/point variants
      differ from tumor to tumor rather than converging on one driver.
  - reference: PMID:11592101
    reference_title: "Adamantinoma-like Ewing's sarcoma and Ewing's-like adamantinoma. The t(11; 22), t(21; 22) status"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      This study investigated the putative presence of t(11; 22) and
      t(21; 22) in 14 cases of adamantinoma by RT-PCR. These translocations
      were not found in any of these cases.
    explanation: >-
      Shows true adamantinoma lacks the EWSR1 translocations that define
      its principal molecular mimic, adamantinoma-like Ewing sarcoma,
      supporting genomic distinctness despite morphologic overlap.

- name: Local Cortical Bone Destruction and Structural Compromise
  biological_scale: TISSUE
  description: >-
    Progressive intracortical and intramedullary tumor growth within the
    tibial diaphysis destroys and thins cortical bone, producing anterior
    tibial bowing, a palpable mass, bone pain, and, in advanced or
    long-standing disease, structural weakening predisposing to pathologic
    fracture.
  locations:
  - preferred_term: tibial diaphysis
    term:
      id: UBERON:0013280
      label: diaphysis of tibia
  downstream:
  - target: Tibial Bowing
    description: Cortical destruction and remodeling produce progressive anterior bowing of the tibia.
  - target: Bone Pain
    description: Local tumor growth and cortical destruction cause chronic bone pain.
  - target: Localized Extremity Mass
    description: Tumor expansion produces a palpable soft-tissue swelling over the involved bone.
  - target: Pathologic Fracture
    description: Cortical thinning from tumor growth predisposes to fracture through the involved bone.
  evidence:
  - reference: PMID:30844202
    reference_title: "Adamantinoma"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Adamantinomas are rare, low-grade malignant bone tumors of uncertain
      histogenesis that predominately affect the diaphyses and metaphyses
      of the tibia.
    explanation: Establishes the anatomic site of the destructive tumor process.

- name: Local Recurrence After Incomplete Surgical Resection
  biological_scale: TISSUE
  description: >-
    Local recurrence is common and can occur late (documented beyond 15
    years post-treatment). Across a synthesized literature base, local
    recurrence rates range from 15-31% for classic adamantinoma and
    22-43% for the OFD-like variant. Wide resection with uncontaminated
    margins is the most consistently protective surgical variable
    identified across the case-series literature; intralesional or
    marginal margins predispose to recurrence.
  downstream:
  - target: Hematogenous and Lymphatic Metastasis
    description: >-
      Recurrent and spindle/basaloid-pattern classic adamantinoma is
      disproportionately associated with subsequent metastatic disease.
  evidence:
  - reference: PMID:42496518
    reference_title: "Adamantinoma of Bone: A Structured Narrative Review of Clinical Outcomes, Recurrence Patterns, and Metastatic Behaviour"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Local recurrence rates for classic adamantinoma (AD) range from 15%
      to 31%, with metastatic rates from 10% to 27%, predominantly to the
      lung.
    explanation: Quantifies the recurrence and metastasis rates from a synthesis of the case-series literature.
  - reference: PMID:42496518
    reference_title: "Adamantinoma of Bone: A Structured Narrative Review of Clinical Outcomes, Recurrence Patterns, and Metastatic Behaviour"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Wide resection with uncontaminated margins is the most consistently
      protective surgical variable (hazard ratio 0.164; p < 0.001).
    explanation: Quantifies the protective effect of margin status on outcome.
  - reference: PMID:42496518
    reference_title: "Adamantinoma of Bone: A Structured Narrative Review of Clinical Outcomes, Recurrence Patterns, and Metastatic Behaviour"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Late recurrences beyond 15 years are documented in multiple series, supporting prolonged surveillance."
    explanation: Documents the long natural history requiring lifelong surveillance.
  - reference: PMID:41653544
    reference_title: "Clinicopathological analysis of osteofibrous dysplasia and adamantinoma: A single institution experience"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The most commonly associated patterns with recurrences and
      metastasis in a classic adamantinoma were spindle and basaloid.
    explanation: Links specific classic-adamantinoma growth patterns to a higher risk of recurrence and metastasis.

- name: Hematogenous and Lymphatic Metastasis
  biological_scale: ORGANISM
  description: >-
    Classic adamantinoma metastasizes predominantly to the lungs, in an
    estimated 10-27% of cases, but metastatic spread is not confined to
    the lung: it is also reported to regional lymph nodes (including a
    case with inguinal nodal recurrence and no pulmonary disease at all)
    and, less commonly, to abdominal/pelvic sites, liver, brain, and
    skeleton. In contrast, the OFD-like variant, despite a locally
    aggressive recurrence rate, shows no metastases in series that report
    it separately, indicating a biologically distinct clinical behavior
    from classic adamantinoma despite their morphologic overlap.
  locations:
  - preferred_term: lung
    term:
      id: UBERON:0002048
      label: lung
  - preferred_term: lymph node
    term:
      id: UBERON:0000029
      label: lymph node
  downstream:
  - target: Pulmonary Metastasis
    description: Hematogenous spread establishes secondary tumor deposits in the lung.
  - target: Nodal Metastasis
    description: Lymphatic spread establishes secondary tumor deposits in regional lymph nodes.
  evidence:
  - reference: PMID:42496518
    reference_title: "Adamantinoma of Bone: A Structured Narrative Review of Clinical Outcomes, Recurrence Patterns, and Metastatic Behaviour"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The osteofibrous dysplasia-like subtype (OFD-AD) showed no
      metastases in any series that reports this subtype separately but
      carries a locally aggressive recurrence rate of 22-43%.
    explanation: >-
      Directly supports the biological distinction between classic
      adamantinoma metastatic potential and the OFD-like variant's purely
      local aggressiveness.
  - reference: PMID:42496518
    reference_title: "Adamantinoma of Bone: A Structured Narrative Review of Clinical Outcomes, Recurrence Patterns, and Metastatic Behaviour"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Because metastatic spread is not confined to the lung, chest CT
      alone may be insufficient for surveillance in selected high-risk
      patients, in whom staging beyond the chest should be considered
    explanation: >-
      Directly supports that metastatic spread extends beyond the lung
      alone, motivating the broader nodal/abdominal-pelvic framing of this
      node rather than a pulmonary-only model.
  - reference: PMID:41653544
    reference_title: "Clinicopathological analysis of osteofibrous dysplasia and adamantinoma: A single institution experience"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Five out of 28 (17.9%) patients with an adamantinoma developed recurrences and 5 (17.9) developed metastases."
    explanation: Independent single-institution series quantifying metastatic frequency among classic adamantinomas.
  - reference: PMID:39555331
    reference_title: "Adamantinoma: A SEER-based Epidemiological Analysis"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      metastasis occurs at rates as high as 18–32% primarily to lymph
      nodes or lungs
    explanation: >-
      Directly establishes lymph nodes, alongside lungs, as a primary
      metastatic site for adamantinoma.
  - reference: PMID:38486378
    reference_title: "Rare Case of Recurrent Adamantinoma of the Tibia: Limited Efficacy of Pazopanib as a Standalone Treatment"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      a positive emission tomography scan revealed mildly increased
      tracer uptake near the area of the previous lesion and in the right
      inguinal lymph node. Biopsies of the lesion and inguinal lymph node
      confirmed recurrence of the adamantinoma. Due to abdominal and
      pelvic metastasis
    explanation: >-
      Case-level evidence of inguinal lymph node and abdominal/pelvic
      metastatic recurrence with no lung involvement reported, directly
      motivating a nodal (not pulmonary-only) metastasis model.

- name: Sarcomatoid Dedifferentiation with Loss of Epithelial Phenotype
  biological_scale: CELLULAR
  mechanism_confidence: PROVISIONAL
  description: >-
    Rarely, classic adamantinoma undergoes high-grade sarcomatoid
    transformation, with progressive loss of pankeratin and other
    epithelial marker expression in the transformed component (a
    "revertant mesenchymal phenotype"). This dedifferentiated form behaves
    more aggressively; the evidence base for its mechanism is limited to a
    small number of case reports.
  evidence:
  - reference: PMID:20717000
    reference_title: "Dedifferentiated classic adamantinoma of the tibia: a report of a case with eventual complete revertant mesenchymal phenotype"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      On the en bloc resection specimen, areas of classic adamantinoma
      were found but most of the tumor corresponded to a high-grade
      neoplasm with 2 histologic patterns: one made up by epithelial nests
      with a basaloid arrangement and positive for pankeratins and
      so-called glandular keratins, and a second sarcomatoid component,
      negative for these epithelial markers.
    explanation: Direct description of a dedifferentiated adamantinoma with sarcomatoid loss of the epithelial immunophenotype.
  downstream:
  - target: Hematogenous and Lymphatic Metastasis
    description: >-
      Dedifferentiated/sarcomatoid transformation is associated with more
      aggressive, higher-risk clinical behavior including relapse and
      metastasis in reported cases.

phenotypes:
- name: Tibial Bowing
  category: Skeletal
  description: >-
    Progressive anterior angular deformity (bowing) of the tibia, a
    recognized presenting or associated finding across the OFD/adamantinoma
    spectrum, particularly well documented for the OFD and OFD-like end of
    that spectrum and in younger patients.
  phenotype_term:
    preferred_term: Tibial bowing
    term:
      id: HP:0002982
      label: Tibial bowing
  evidence:
  - reference: PMID:35094574
    reference_title: "Osteofibrous dysplasia of the tibia : the importance of deformity in surveillance"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      41 lesions (40.6%) presented with radiological deformity (> 10°):
      apex anterior in 97.6%.
    explanation: >-
      Directly quantifies anterior angular tibial deformity (bowing) in a
      101-lesion tibial OFD case series, the benign end of the
      OFD/adamantinoma spectrum this phenotype describes.
  - reference: PMID:38539216
    reference_title: "Osteofibrous dysplasia: a narrative review"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      OFD can present with asymptomatic, mass, pain, swelling, deformity
      (anterior bowing of the tibia), and even pathological fracture
    explanation: >-
      Independent narrative review confirming anterior tibial bowing
      (deformity) as a recognized clinical presentation across the
      OFD/adamantinoma spectrum.

- name: Bone Pain
  category: Musculoskeletal
  description: >-
    Local pain over the involved tibial segment, a common presenting
    complaint, typically accompanying a palpable mass.
  phenotype_term:
    preferred_term: Bone pain
    term:
      id: HP:0002653
      label: Bone pain
  evidence:
  - reference: PMID:39555331
    reference_title: "Adamantinoma: A SEER-based Epidemiological Analysis"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "patients typically present with a painful, swollen mass which can be palpated."
    explanation: Direct support for pain as a common presenting feature.

- name: Localized Extremity Mass
  category: Musculoskeletal
  description: >-
    A palpable mass or swelling overlying the involved bone, typically
    accompanying bone pain rather than presenting painlessly.
  phenotype_term:
    preferred_term: Localized soft-tissue mass of the leg
    term:
      id: HP:6000840
      label: Localized soft-tissue swelling on extremity
  evidence:
  - reference: PMID:39555331
    reference_title: "Adamantinoma: A SEER-based Epidemiological Analysis"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "patients typically present with a painful, swollen mass which can be palpated."
    explanation: Direct support for a palpable mass as a common presenting feature.

- name: Pathologic Fracture
  category: Musculoskeletal
  description: >-
    Fracture through bone weakened by tumor-related cortical destruction;
    reported at presentation in 10-21% of cases across series, and an
    independent predictor of local recurrence.
  phenotype_term:
    preferred_term: Pathologic fracture
    term:
      id: HP:0002756
      label: Pathologic fracture
  evidence:
  - reference: PMID:42496518
    reference_title: "Adamantinoma of Bone: A Structured Narrative Review of Clinical Outcomes, Recurrence Patterns, and Metastatic Behaviour"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Pathological fracture at presentation was recorded in 10% to 21%
      across series
    explanation: Quantifies pathologic fracture frequency at presentation.

- name: Bone Neoplasm
  category: Neoplastic
  description: >-
    A primary bone neoplasm, almost always centered in the tibial
    diaphysis or metaphysis.
  phenotype_term:
    preferred_term: Adamantinoma of bone
    term:
      id: HP:0010622
      label: Neoplasm of the skeletal system

- name: Osteolytic Bone Lesion
  category: Skeletal
  description: >-
    Radiographically, the tumor characteristically appears as a lytic
    (osteolytic) lesion with sclerotic margins and overlapping
    radiolucency, producing the classic "soap-bubble" appearance (see
    `diagnosis#Plain Radiography (Soap-Bubble Osteolytic Lesion)`).
  phenotype_term:
    preferred_term: Osteolytic soap-bubble lesion of the tibia
    term:
      id: HP:0002797
      label: Osteolysis
  evidence:
  - reference: PMID:34697136
    reference_title: "Adamantinoma: An Updated Review"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In X-ray, it is usually seen as an eccentric and sometimes central,
      lobular, lytic lesion with sclerotic margins of overlapping
      radiolucency, and a characteristic 'soap-bubble' appearance.
    explanation: Direct description of the characteristic osteolytic radiographic appearance.

- name: Pulmonary Metastasis
  category: Neoplastic
  description: >-
    Hematogenous metastasis to the lung, reported in approximately 10-27%
    of classic adamantinoma cases; not reported for the OFD-like variant
    in series reporting it separately.
  phenotype_term:
    preferred_term: Pulmonary metastasis of adamantinoma
    term:
      id: HP:0100526
      label: Neoplasm of the lung
  evidence:
  - reference: PMID:42496518
    reference_title: "Adamantinoma of Bone: A Structured Narrative Review of Clinical Outcomes, Recurrence Patterns, and Metastatic Behaviour"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Local recurrence rates for classic adamantinoma (AD) range from 15%
      to 31%, with metastatic rates from 10% to 27%, predominantly to the
      lung.
    explanation: Direct support for lung as the predominant metastatic site.

- name: Nodal Metastasis
  category: Neoplastic
  description: >-
    Metastasis to regional lymph nodes, reported as a primary metastatic
    site alongside the lungs; a documented case shows nodal (inguinal)
    recurrence with abdominal/pelvic spread and no pulmonary involvement,
    so this is not simply a rarer variant of pulmonary spread.
  phenotype_term:
    preferred_term: Lymph node metastasis of adamantinoma
    term:
      id: HP:0002733
      label: Abnormal lymph node morphology
  evidence:
  - reference: PMID:39555331
    reference_title: "Adamantinoma: A SEER-based Epidemiological Analysis"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      metastasis occurs at rates as high as 18–32% primarily to lymph
      nodes or lungs
    explanation: Directly establishes lymph nodes as a primary metastatic site.
  - reference: PMID:38486378
    reference_title: "Rare Case of Recurrent Adamantinoma of the Tibia: Limited Efficacy of Pazopanib as a Standalone Treatment"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      a positive emission tomography scan revealed mildly increased
      tracer uptake near the area of the previous lesion and in the right
      inguinal lymph node. Biopsies of the lesion and inguinal lymph node
      confirmed recurrence of the adamantinoma
    explanation: Case-level confirmation of inguinal lymph node metastatic recurrence.

histopathology:
- name: Keratin/p63-Positive Epithelial Immunoprofile
  diagnostic: true
  description: >-
    The neoplastic epithelial nests express pankeratin (AE1/AE3) in
    approximately 95% of cases, with p40 and p63 also positive in the
    large majority of cases; this keratin/p63 epithelial immunoprofile
    within an otherwise osteofibrous bone lesion is the diagnostic anchor
    that establishes an epithelial (rather than purely mesenchymal or
    fibro-osseous) neoplasm.
  finding_term:
    preferred_term: Cytokeratin and p63 co-expression in epithelial tumor nests
    term:
      id: NCIT:C81765
      label: Cytokeratin-Positive Neoplastic Cells Present
  frequency: VERY_FREQUENT
  evidence:
  - reference: PMID:41653544
    reference_title: "Clinicopathological analysis of osteofibrous dysplasia and adamantinoma: A single institution experience"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Pan keratin (AE1/AE3) was positive in 18/19 (94.7%) OFDs and 19/20
      (95%) adamantinomas. P40 (5/5, 100%) and p63 (6/8, 75%) were useful
      in the diagnosis of adamantinoma.
    explanation: Direct quantification of pankeratin/p40/p63 positivity rates.
  - reference: PMID:21674157
    reference_title: "p63 expression in adamantinoma"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The epithelial component in adamantinoma was found to stain for p63."
    explanation: Establishes p63 as a marker of the epithelial tumor component.

- name: Tubular/Basaloid/Spindle-Cell/Squamoid Growth Patterns (Classic Adamantinoma)
  diagnostic: true
  description: >-
    Classic adamantinoma displays a spectrum of architectural growth
    patterns — tubular, basaloid, spindle-cell, and squamoid — within the
    same underlying epithelial-osteofibrous biphasic lesion. The keratin
    immunoreactivity pattern is conserved across all of these patterns,
    indicating a shared histogenesis; spindle and basaloid patterns are
    disproportionately associated with recurrence and metastasis.
  finding_term:
    preferred_term: Tubular growth pattern
    term:
      id: NCIT:C35925
      label: Tubular Pattern
  evidence:
  - reference: PMID:7694513
    reference_title: "Adamantinoma of the long bones: keratin subclass immunoreactivity pattern with reference to its histogenesis"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      This keratin immunoreactivity pattern was independent of histologic
      subtype, despite marked variety in differentiation pattern,
      suggesting a common histogenesis for all subtypes of adamantinoma.
    explanation: >-
      Directly supports that the growth-pattern variants share a common
      histogenesis rather than being distinct entities.
  - reference: PMID:41653544
    reference_title: "Clinicopathological analysis of osteofibrous dysplasia and adamantinoma: A single institution experience"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The most commonly associated patterns with recurrences and
      metastasis in a classic adamantinoma were spindle and basaloid.
    explanation: Links specific growth patterns to prognostic behavior.

- name: Osteofibrous Dysplasia-Like Pattern
  diagnostic: false
  description: >-
    A fibro-osseous pattern resembling osteofibrous dysplasia, with only
    scattered or focal keratin/p40-positive epithelial cell clusters
    (sometimes detectable only by immunostain, not on light microscopy).
    Distinguishing an OFD-like adamantinoma from osteofibrous dysplasia
    proper, and from classic adamantinoma, is a recognized source of
    interobserver diagnostic disagreement (see `discussions`).
  finding_term:
    preferred_term: Osteofibrous dysplasia-like growth pattern
  evidence:
  - reference: PMID:42379271
    reference_title: "Genomic Characterization of Classic Adamantinoma, Osteofibrous Dysplasia, and Osteofibrous Dysplasia-like Adamantinoma"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      one case with tumor clusters visible only on cytokeratin immunostain
      harbored no variants, whereas another case with tumor clusters
      visible on light microscopy and cytokeratin/p40 immunostains showed
      gains of chromosome 7, 8, 19, and 20
    explanation: >-
      Documents the diagnostically ambiguous, immunostain-dependent nature
      of the OFD-like epithelial component.
  - reference: PMID:41653544
    reference_title: "Clinicopathological analysis of osteofibrous dysplasia and adamantinoma: A single institution experience"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      After a review, the diagnosis was modified in 12/58 (20.7%) tumors;
      with 4 OFDs revised to FDs; 2 FDs to OFDs; 2 intra-osseous SSs to
      classic adamantinomas; 3 OFD-like adamantinomas to classic
      adamantinomas, and a single de-differentiated adamantinoma to
      classic adamantinoma.
    explanation: >-
      Quantifies the substantial rate of diagnostic revision among OFD,
      OFD-like adamantinoma, and classic adamantinoma on expert review,
      supporting that these categories are diagnostically unstable rather
      than sharply demarcated entities.

- name: Sarcomatoid Dedifferentiation
  diagnostic: false
  description: >-
    A rare high-grade component with loss of epithelial (keratin) marker
    expression arising within or after classic adamantinoma, sometimes
    with a completely "revertant" mesenchymal/sarcomatoid phenotype on
    recurrence.
  finding_term:
    preferred_term: Sarcomatoid dedifferentiation
    term:
      id: NCIT:C158781
      label: Dedifferentiated Lesion
  frequency: VERY_RARE
  evidence:
  - reference: PMID:20717000
    reference_title: "Dedifferentiated classic adamantinoma of the tibia: a report of a case with eventual complete revertant mesenchymal phenotype"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Three cases of adamantinomas with sarcomatoid transformation of the
      epithelial component have been described but the tumours still
      preserved an epithelial immunophenotype.
    explanation: Establishes the rarity and prior documentation of dedifferentiation in adamantinoma.

diagnosis:
- name: Plain Radiography (Soap-Bubble Osteolytic Lesion)
  description: >-
    Initial imaging is plain radiography, which characteristically shows
    an eccentric, lobular, lytic lesion with sclerotic margins of
    overlapping radiolucency in the tibial diaphysis -- the classic
    "soap-bubble" appearance -- though the radiologic impression does not
    reliably predict the underlying histologic diagnosis (see the
    centrally-sampled-biopsy caveat below).
  diagnosis_term:
    preferred_term: plain radiography of the affected bone
    term:
      id: NCIT:C38101
      label: X-Ray Imaging
  evidence:
  - reference: PMID:34697136
    reference_title: "Adamantinoma: An Updated Review"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In X-ray, it is usually seen as an eccentric and sometimes central,
      lobular, lytic lesion with sclerotic margins of overlapping
      radiolucency, and a characteristic 'soap-bubble' appearance.
    explanation: Direct description of the characteristic radiographic appearance.

- name: Whole-Bone MRI for Multifocality and Skip Lesions
  description: >-
    MRI of the entire involved bone is used both for differential
    diagnosis and to detect multifocal disease -- reported in
    approximately 24% of cases -- including a singular lobulated focus or
    several small nodules within multiple foci that may not be apparent on
    plain radiographs alone.
  diagnosis_term:
    preferred_term: magnetic resonance imaging of the affected bone
    term:
      id: NCIT:C16809
      label: Magnetic Resonance Imaging
  evidence:
  - reference: PMID:38486378
    reference_title: "Rare Case of Recurrent Adamantinoma of the Tibia: Limited Efficacy of Pazopanib as a Standalone Treatment"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      On magnetic resonance imaging (MRI), 2 morphological patterns have
      been described: a singular lobulated focus or several small nodules
      within multiple foci.
    explanation: Directly describes the multifocal/skip-lesion MRI patterns relevant to whole-bone imaging.
  - reference: PMID:42496518
    reference_title: "Adamantinoma of Bone: A Structured Narrative Review of Clinical Outcomes, Recurrence Patterns, and Metastatic Behaviour"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Multifocality occurs in approximately 24% of cases"
    explanation: Quantifies the frequency of multifocal disease that whole-bone MRI is intended to detect.
  - reference: PMID:34697136
    reference_title: "Adamantinoma: An Updated Review"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Magnetic resonance imaging seems to be the most appropriate
      examination for differential diagnosis between adamantinoma and
      other skeletal tumors.
    explanation: Establishes MRI as the preferred differential-diagnosis imaging modality.

- name: Chest CT for Metastatic Staging
  description: >-
    Chest CT is used for pulmonary metastatic staging given the tumor's
    predilection for hematogenous lung spread, but chest CT alone can be
    insufficient in high-risk patients because metastatic spread is not
    confined to the lung (see `phenotypes#Nodal Metastasis`); staging
    beyond the chest should be considered in selected high-risk cases, and
    the optimal imaging modality, extent, and frequency of surveillance
    remain undefined.
  diagnosis_term:
    preferred_term: computed tomography of the chest
    term:
      id: NCIT:C17204
      label: Computed Tomography
  evidence:
  - reference: PMID:42496518
    reference_title: "Adamantinoma of Bone: A Structured Narrative Review of Clinical Outcomes, Recurrence Patterns, and Metastatic Behaviour"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Because metastatic spread is not confined to the lung, chest CT
      alone may be insufficient for surveillance in selected high-risk
      patients, in whom staging beyond the chest should be considered
    explanation: Directly supports both the chest-CT staging role and its limitation given non-pulmonary metastatic sites.

- name: Centrally-Sampled Biopsy with Immunohistochemistry
  description: >-
    Because the diagnostic epithelial component can be sparse and
    patchy -- especially in OFD-like adamantinoma, where it may be
    detectable only by immunostain and not on light microscopy (see
    `histopathology#Osteofibrous Dysplasia-Like Pattern`) -- adequate,
    ideally centrally-sampled biopsy with immunohistochemistry (pankeratin,
    p40, p63) is needed to avoid false-negative or misclassified
    diagnoses; radiologic-histologic concordance is imperfect even among
    experienced centers.
  diagnosis_term:
    preferred_term: image-guided biopsy with immunohistochemistry
    term:
      id: NCIT:C15189
      label: Biopsy Procedure
  evidence:
  - reference: PMID:18279517
    reference_title: "Adamantinoma: a clinicopathological review and update"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      To assure the histological diagnosis, pathologists should employ
      immunohistochemistry for demonstrating the sometimes sparse
      epithelial cell nests when the radiological features are suggestive
      of adamantinoma.
    explanation: Directly states the sampling/immunohistochemistry caveat for the sparse epithelial component.
  - reference: PMID:41653544
    reference_title: "Clinicopathological analysis of osteofibrous dysplasia and adamantinoma: A single institution experience"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The radiological impression concurred with the histopathological diagnosis in 40% of OFDs and 60% of adamantinomas."
    explanation: Quantifies imperfect radiologic-histologic concordance, motivating reliance on adequately sampled biopsy.

treatments:
- name: Wide En Bloc Surgical Resection
  description: >-
    Complete surgical excision with uncontaminated (wide) margins is the
    standard, and most consistently effective, treatment for adamantinoma.
    Conventional chemotherapy and radiotherapy have not been shown to be
    reliably effective, so margin-negative surgery is the primary
    curative-intent modality; reconstruction (e.g., with a vascularized
    fibular graft) is frequently required for the resulting tibial defect.
  treatment_term:
    preferred_term: en bloc surgical resection
    term:
      id: NCIT:C139567
      label: En Bloc Resection
  evidence:
  - reference: PMID:42496518
    reference_title: "Adamantinoma of Bone: A Structured Narrative Review of Clinical Outcomes, Recurrence Patterns, and Metastatic Behaviour"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Wide resection with uncontaminated margins is the most consistently
      protective surgical variable (hazard ratio 0.164; p < 0.001).
    explanation: Quantifies the protective effect of wide-margin resection on recurrence risk.

- name: Limb-Sparing Reconstruction
  description: >-
    Following wide resection of the tibial defect, limb-sparing
    reconstructive techniques (including vascularized or non-vascularized
    fibular grafts) are used to preserve limb function and avoid
    amputation where feasible.
  treatment_term:
    preferred_term: limb salvage procedure
    term:
      id: NCIT:C16042
      label: Limb Salvage Procedure

- name: Pazopanib (Limited Efficacy in Recurrent/Metastatic Disease)
  description: >-
    The multi-target tyrosine kinase inhibitor pazopanib has been used in
    recurrent/metastatic adamantinoma when surgery alone is no longer
    curative, but case-level experience to date indicates limited
    standalone efficacy; adamantinoma has no consensus systemic-therapy
    guideline.
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: pazopanib
      term:
        id: CHEBI:71219
        label: pazopanib
  evidence:
  - reference: PMID:38486378
    reference_title: "Rare Case of Recurrent Adamantinoma of the Tibia: Limited Efficacy of Pazopanib as a Standalone Treatment"
    supports: REFUTE
    evidence_source: HUMAN_CLINICAL
    snippet: "This report showed that pazopanib as standalone treatment does not appear to have promising role on patient outcomes."
    explanation: >-
      Case report directly reporting limited efficacy of pazopanib
      monotherapy for recurrent/metastatic adamantinoma.
  notes: >-
    A separate case report describes a sustained response to the PARP
    inhibitor olaparib in a metastatic adamantinoma harboring a somatic
    XRCC2 frameshift mutation (PMID:41370129), illustrating an emerging,
    genomically-guided precision-oncology approach for individual
    metastatic cases; this is not yet an established or guideline-based
    treatment and is not modeled as a separate targeted-therapy entry
    given the single-case evidence base.

differential_diagnoses:
- name: Ameloblastoma
  description: >-
    Ameloblastoma is a locally aggressive odontogenic epithelial tumor of
    the jaw (mandible/maxilla) that shares keratin-positive epithelial
    histology with adamantinoma of long bone, and historically gave
    adamantinoma its name, but the two are anatomically, embryologically,
    and clinically distinct entities: ameloblastoma arises from odontogenic
    epithelium in the jaw, whereas adamantinoma is a primary bone tumor
    with a striking predilection for the tibial diaphysis and no
    odontogenic relationship. This entry (MONDO:0002422) is NOT
    ameloblastoma (MONDO:0017795).
  disease_term:
    preferred_term: ameloblastoma
    term:
      id: MONDO:0017795
      label: ameloblastoma
  distinguishing_features:
  - Arises in the jaw (mandible/maxilla) from odontogenic epithelium, not in long bones
  - No predilection for the tibial diaphysis
  - Distinct molecular drivers (e.g., BRAF V600E, SMO) not reported as recurrent in true adamantinoma
  evidence:
  - reference: PMID:30844202
    reference_title: "Adamantinoma"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      The tumor is called adamantinoma due to its histological similarity
      to ameloblastoma, often found in the mandible.
    explanation: >-
      States the historical basis for the name shared with ameloblastoma
      while identifying the mandible as the site specific to ameloblastoma.

- name: Adamantinomatous Craniopharyngioma
  description: >-
    Adamantinomatous craniopharyngioma is a WHO grade 1 epithelial
    neoplasm of the sellar/parasellar region arising from Rathke pouch
    epithelial remnants, driven by somatic CTNNB1 mutations. It shares
    only a descriptive histological label ("adamantinomatous," for its
    resemblance to ameloblastoma/adamantinoma-type epithelium) with the
    bone tumor curated in this entry; it is a completely separate
    disease, already curated in dismech as `Craniopharyngioma.yaml`, and
    is not a form of, subtype of, or related to skeletal adamantinoma
    (MONDO:0002422).
  disease_term:
    preferred_term: craniopharyngioma
    term:
      id: MONDO:0018907
      label: craniopharyngioma
  distinguishing_features:
  - Arises in the sellar/suprasellar region of the central nervous system, not in bone
  - Driven by somatic CTNNB1/Wnt pathway activation, not by the chromosomal copy-number gains seen in skeletal adamantinoma
  - Presents with visual, endocrine, and hypothalamic symptoms rather than a limb mass or bone pain
  notes: >-
    Named entity confusion risk: "adamantinoma" and "adamantinomatous
    craniopharyngioma" share only the descriptive adjective, not disease
    identity; deep-research and literature-search tools can conflate them.

- name: Adamantinoma-like Ewing Sarcoma
  description: >-
    A member of the Ewing sarcoma family of tumors that shows aberrant
    epithelial (cytokeratin) expression and, in some cases, an
    architectural resemblance to adamantinoma, but is genetically defined
    by the canonical Ewing sarcoma EWSR1::FLI1 t(11;22) or EWSR1::ERG
    t(21;22) translocation. These translocations are consistently absent
    in true adamantinoma, despite the misleading shared name.
  distinguishing_features:
  - Carries the EWSR1::FLI1 t(11;22) or EWSR1::ERG t(21;22) translocation, absent in true adamantinoma
  - Not restricted to the tibial diaphysis in the same site-specific pattern as adamantinoma
  - Aggressive small round blue cell histology rather than the biphasic epithelial-osteofibrous pattern of adamantinoma
  evidence:
  - reference: PMID:11592101
    reference_title: "Adamantinoma-like Ewing's sarcoma and Ewing's-like adamantinoma. The t(11; 22), t(21; 22) status"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      This study investigated the putative presence of t(11; 22) and
      t(21; 22) in 14 cases of adamantinoma by RT-PCR. These translocations
      were not found in any of these cases. The results support the view
      that these tumours are genetically and clinically distinct, but may
      eventually show overlapping morphological and immunohistochemical
      features.
    explanation: >-
      Directly establishes the genetic distinction between true
      adamantinoma and adamantinoma-like Ewing sarcoma despite
      morphologic overlap.

- name: Osteofibrous Dysplasia
  description: >-
    A benign, self-limited fibro-osseous lesion of the tibial diaphysis in
    children, radiologically and histologically similar to OFD-like
    adamantinoma; distinguishing the two (and determining whether OFD can
    itself progress to adamantinoma) is an open diagnostic and
    histogenetic question (see `discussions`).
  disease_term:
    preferred_term: osteofibrous dysplasia
    term:
      id: MONDO:0011806
      label: osteofibrous dysplasia
  distinguishing_features:
  - Benign lesion, historically not considered to metastasize
  - Typically younger age at presentation (median 10 years vs 25 years for adamantinoma in one series)
  - Absent or only very focal/rare p63-positive epithelial cells on immunostain
  evidence:
  - reference: PMID:41653544
    reference_title: "Clinicopathological analysis of osteofibrous dysplasia and adamantinoma: A single institution experience"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The median age for OFD (10 years) was lower than that of adamantinoma (25 years)."
    explanation: Quantifies the age-distribution distinction used to help separate the two entities clinically.

discussions:
- discussion_id: adam_ofd_progression_sequence
  prompt: >-
    Does osteofibrous dysplasia progress through an OFD-like adamantinoma
    intermediate to classic adamantinoma along a single histogenetic
    continuum, or are these three diagnostically overlapping but
    biologically separate entities?
  kind: KNOWLEDGE_GAP
  status: OPEN
  attaches_to:
  - pathophysiology#Biphasic Epithelial-Osteofibrous Neoplastic Proliferation
  - pathophysiology#Recurrent Chromosomal Copy-Number Gains Without an Established Driver
  - histopathology#Osteofibrous Dysplasia-Like Pattern
  - differential_diagnoses#Osteofibrous Dysplasia
  rationale: >-
    Shared cytogenetic findings (trisomies 7, 8, and 12 reported in both
    OFD and adamantinoma) and shared, if focal, p63/keratin epithelial
    positivity in OFD have long been read as evidence of a common
    histogenesis and a possible progression sequence from OFD through
    OFD-like adamantinoma to classic adamantinoma. However, a contemporary
    genomic comparison found classic adamantinomas carry multiple
    chromosome/arm-level copy-number gains that OFDs largely lack, arguing
    the two may be genetically distinct rather than points on one
    continuum; and the largest recent single-institution clinicopathologic
    series observed a morphological continuum among the three diagnoses
    but did not observe any OFD progressing to adamantinoma during
    prospective follow-up (median 51 months, range 4-98 months). Both the
    "shared histogenesis/progression" and "distinct entities" readings
    remain live in the literature, and no study to date has followed a
    cohort of confirmed OFD cases long enough, with sufficiently
    consistent molecular workup, to settle the question. This bears
    directly on clinical management: if OFD can progress to a malignant
    tumor, that argues for closer surveillance of pediatric OFD than is
    currently standard.
  proposed_experiments:
  - experiment_id: exp_adam_ofd_longitudinal_molecular_cohort
    name: Prospective longitudinal molecular cohort of OFD, OFD-like adamantinoma, and classic adamantinoma
    description: >-
      Assemble a multi-institutional cohort of histologically confirmed
      OFD cases with long-term (>15 year) clinical and radiographic
      follow-up, paired with serial genomic profiling (copy-number/SNP
      array or targeted sequencing) of the lesion at diagnosis and at any
      subsequent biopsy or recurrence, to determine whether any lesion
      acquires the classic-adamantinoma copy-number gain pattern over time
      and whether that acquisition precedes clinical/histologic
      progression.
  evidence:
  - reference: PMID:9242211
    reference_title: "Cytogenetic analysis of adamantinoma of long bones: further indications for a common histogenesis with osteofibrous dysplasia"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The trisomies 7, 8, and 12 also were described in OFD, which
      suggests a common histogenesis of OFD and adamantinoma.
    explanation: Represents the "shared histogenesis/progression" position in the literature.
  - reference: PMID:12679847
    reference_title: "Adamantinoma, osteofibrous dysplasia and differentiated adamantinoma"
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      Cytokeratin subset immunohistochemical stains and cytogenetic
      studies performed in recent years suggest a common histogenesis for
      these three entities.
    explanation: >-
      Independent review reinforcing the "shared histogenesis/progression"
      position across OFD, OFD-like adamantinoma, and classic
      adamantinoma.
  - reference: PMID:42379271
    reference_title: "Genomic Characterization of Classic Adamantinoma, Osteofibrous Dysplasia, and Osteofibrous Dysplasia-like Adamantinoma"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In conclusion, classic adamantinomas and OFD might be genetically
      distinct. Classic adamantinomas harbored multiple alterations,
      including chromosome/arm-level copy number gains, the detection of
      which could aid their distinction from OFDs.
    explanation: >-
      Represents the more recent, genomically-based "distinct entities"
      position, in tension with the earlier common-histogenesis reading.
  - reference: PMID:41653544
    reference_title: "Clinicopathological analysis of osteofibrous dysplasia and adamantinoma: A single institution experience"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Although there is a morphological continuum between OFD and
      adamantinoma, we did not observe a disease progression during the
      limited follow-up.
    explanation: >-
      Direct negative result on progression from the largest recent
      clinicopathologic follow-up series, explicitly framed against the
      morphological-continuum hypothesis.
📚

References & Deep Research

Deep Research

1
Falcon
Adamantinoma of Long Bones: Disease-Characteristics Research Report
Edison Scientific Literature 25 citations 2026-08-26T16:48:56.985226

Adamantinoma of Long Bones: Disease-Characteristics Research Report

Scope and evidence note

This report concerns adamantinoma of long bones, not ameloblastoma of the jaw, adamantinomatous craniopharyngioma, or adamantinoma-like Ewing sarcoma (ALES). Those are biologically distinct entities whose similar names commonly produce database-search false positives. Evidence for adamantinoma is limited by extreme rarity; much of the quantitative literature consists of retrospective referral-center series, pathology cohorts, case reports, and narrative reviews rather than prospective trials.

The most useful recent sources retrieved were Węgrzyniak et al., published 30 August 2023 (DOI: 10.12775/JEHS.2023.47.01.003), and Monteiro et al., accepted 9 February 2024. The major primary clinical benchmark remains Keeney et al.’s 85-case series, published 1 August 1989 (DOI: 10.1002/1097-0142(19890801)64:3%3C730::AID-CNCR2820640327%3E3.0.CO;2-P).

Domain Evidence-based entry Suggested ontology
Definition/classification Adamantinoma of long bone is a rare primary low-grade malignant bone tumor with biphasic epithelial and osteofibrous components, most often arising in the tibial diaphysis. WHO 2020 places it among “other mesenchymal tumours of bone” and recognizes classic adamantinoma, OFD-like adamantinoma, and dedifferentiated adamantinoma. It is distinct from adamantinoma-like Ewing sarcoma, which is a separate EWSR1/FET-ETS–rearranged round-cell sarcoma mimic rather than true adamantinoma. (wegrzyniak2023currentclinicopathologicalcharacterisation pages 1-5, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9, jain2008adamantinomaaclinicopathological pages 1-2, rekhi2025osteofibrousdysplasia(ofd) pages 8-10) MONDO: adamantinoma (MONDO_0002422); NCIT: Adamantinoma; MeSH: Adamantinoma; UBERON: tibia, fibula; NCIT/WHO class: other mesenchymal tumours of bone
Epidemiology Reported frequency is ~0.1–0.5% of primary bone tumors. Landmark 85-case series: 70/85 tibial, 11 of those with fibular involvement; age range 3–72 years, average 25.9 years; slight male excess (45 male, 39 female, 1 unknown). Reviews summarize typical presentation at 20–40 years, often 25–35 years. (wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9, keeney1989adamantinomaoflong pages 1-2, jain2008adamantinomaaclinicopathological pages 1-2) NCIT: Rare Neoplasm; HPO onset terms: Adult onset, Adolescent onset
Anatomy/localization Strong predilection for long bones (reported 97%), especially tibia (80–85%), usually anterior cortex/diaphysis; ipsilateral fibular involvement in ~10–15%. Rare sites include femur, ulna, humerus, radius, ribs, spine, and pretibial soft tissue. Lesions are often intracortical but may extend into medulla and soft tissue. (jain2008adamantinomaaclinicopathological pages 1-2, jain2008adamantinomaaclinicopathological pages 2-4, keeney1989adamantinomaoflong pages 1-2, keeney1989adamantinomaoflong pages 2-3) UBERON: tibia, fibula, cortical bone, bone marrow, soft tissue; CL: epithelial cell, fibroblast
Phenotype/natural history Presentation is indolent and nonspecific: pain, swelling, stiffness, deformity/bowing, impaired weight-bearing; pathologic fracture reported up to ~23–25%. Course is slow and progressive, with symptoms sometimes present for years before diagnosis; recurrence/metastasis may appear many years later. (jain2008adamantinomaaclinicopathological pages 1-2, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9, keeney1989adamantinomaoflong pages 1-2, kumar2021anunusualcase pages 6-7) HPO: HP:0012531 Pain; HP:0001382 Joint stiffness; HP:0009826 Limb swelling; HP:0000927 Abnormality of the skeletal system; HP:0002757 Pathological fracture
Distinguishing subtypes Classic adamantinoma: usually >20 years, overt epithelial nests in fibrous stroma, more aggressive malignant behavior. OFD-like adamantinoma: usually younger patients/teens, intracortical lesion with sparse keratin-positive epithelial nests often requiring IHC, better prognosis but long follow-up needed; possible progression to classic tumor reported. Dedifferentiated adamantinoma: classic areas plus high-grade sarcomatous component, more aggressive. Adamantinoma-like Ewing sarcoma differs by molecular fusion status and immunophenotype. (wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9, wegrzyniak2023currentclinicopathologicalcharacterisation pages 9-13, jain2008adamantinomaaclinicopathological pages 2-4, rekhi2025osteofibrousdysplasia(ofd) pages 8-10) NCIT: Classic Adamantinoma; NCIT: Dedifferentiated Adamantinoma; NCIT/WHO: Osteofibrous dysplasia-like adamantinoma; NCIT: Ewing Sarcoma
Molecular findings Evidence supports epithelial differentiation with cytokeratin expression. Recurrent cytogenetic copy-number abnormalities/gains involving chromosomes 7, 8, 12, 19, and 21 have been reported. Candidate/nonvalidated tumor findings summarized in recent reviews include KMT2D mutation and increased DLK1 expression; these are research-level, not established clinical drivers. Increased epithelial-cell proliferation markers and EGFR expression relative to stromal component have been proposed. No validated germline causal gene, hereditary syndrome, or standard actionable target is established. (wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9, jain2008adamantinomaaclinicopathological pages 6-8, amr2026managementoftibial pages 4-6) HGNC: KMT2D, DLK1, EGFR, TP53; GO: keratinization/epithelial cell differentiation, cell proliferation; CL: epithelial cell, fibroblast
Pathophysiology Current model is a biphasic neoplasm of epithelial cells embedded in osteofibrous stroma. Reviews propose that the epithelial component is the primary neoplastic population, potentially stimulating stromal proliferation; relation to osteofibrous dysplasia remains debated, with some evidence for a spectrum/continuum in a subset. Mechanistic evidence remains limited and largely histologic/cytogenetic rather than pathway-resolved. (wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9, jain2008adamantinomaaclinicopathological pages 4-5, jain2008adamantinomaaclinicopathological pages 6-8) GO: epithelial cell proliferation, extracellular matrix organization; CL: epithelial cell, fibroblast; UBERON: cortical bone
Diagnosis Diagnosis integrates radiology, biopsy, histology, and IHC. Radiographs typically show multilocular osteolytic lesion with sclerosis and “soap-bubble” appearance; CT defines cortex and pulmonary metastases; MRI is best for intramedullary, cortical, multifocal, and soft-tissue extent. Histology shows epithelial islands/nests/cords in fibrous stroma with tubular, basaloid, squamous, spindle-cell, or OFD-like patterns. Extensive sampling is important, especially for OFD-like lesions. (jain2008adamantinomaaclinicopathological pages 2-4, wegrzyniak2023currentclinicopathologicalcharacterisation pages 9-13, amr2026managementoftibial pages 4-6, monteiro2024adamantinomadetíbia pages 4-6, jain2008adamantinomaaclinicopathological pages 9-10) NCIT: Magnetic Resonance Imaging, Computed Tomography, Radiography, Biopsy; HPO: HP:0031837 Osteolytic lesion
Diagnostic immunophenotype Typical tumor epithelial cells are positive for broad cytokeratins, especially CK5/CK14/CK19, and often p63; EMA may be positive in classic lesions but can be variable. IHC is particularly valuable for detecting sparse epithelial nests in OFD-like lesions and excluding mimics. (jain2008adamantinomaaclinicopathological pages 1-2, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9, amr2026managementoftibial pages 4-6, monteiro2024adamantinomadetíbia pages 4-6) HGNC/Protein markers: KRT5, KRT14, KRT19, TP63, EPCAM/EMA
Differential diagnosis Key differentials: osteofibrous dysplasia, fibrous dysplasia, Ewing sarcoma/adamantinoma-like Ewing sarcoma, osteosarcoma, metastatic carcinoma, vascular tumors, osteomyelitis. OFD is typically strictly intracortical and benign; adamantinoma-like Ewing sarcoma is separated by fusion testing and a different IHC/genetic profile. (jain2008adamantinomaaclinicopathological pages 2-4, jain2008adamantinomaaclinicopathological pages 8-9, wegrzyniak2023currentclinicopathologicalcharacterisation pages 9-13, rekhi2025osteofibrousdysplasia(ofd) pages 8-10) NCIT: Osteofibrous Dysplasia, Fibrous Dysplasia of Bone, Ewing Sarcoma, Osteosarcoma, Carcinoma Metastatic in Bone
Prognosis Landmark series reported local recurrence in 26/85 (31%), lung metastasis in 13/85 (15%), lymph-node metastasis in 6/85 (7%), and disease-specific death in 11 patients. Reviews summarize recurrence ~18–32% and metastasis ~12–30%, often to lung and regional lymph nodes, with very late events possible. Poorer outcomes are associated with male sex, pain, shorter symptom duration, inadequate/intralesional treatment, and lack of squamous differentiation; margin status is a major predictor. (keeney1989adamantinomaoflong pages 1-2, keeney1989adamantinomaoflong pages 6-7, jain2008adamantinomaaclinicopathological pages 6-8, amr2026managementoftibial pages 6-7, kumar2021anunusualcase pages 6-7) NCIT: Local Recurrence, Lung Metastasis, Lymph Node Metastasis, Prognostic Factor
Treatment/current practice Standard treatment is wide en-bloc resection with negative margins, usually with limb-salvage reconstruction when feasible. Amputation is reserved for unresectable recurrence, extensive disease, or reconstructive failure. Chemotherapy and radiotherapy have no established routine benefit in conventional adamantinoma. Reconstruction options reported include allograft, vascularized fibular graft, endoprosthetic approaches, and other limb-salvage methods. (jain2008adamantinomaaclinicopathological pages 6-8, kumar2021anunusualcase pages 6-7, amr2026managementoftibial pages 8-9, monteiro2024adamantinomadetíbia pages 4-6) NCIT: Surgical Resection, Limb Salvage Procedure, Bone Grafting, Amputation
Follow-up/prevention No validated primary-prevention strategy, screening program, or hereditary-risk testing framework is established. Because recurrence and metastasis may occur after long latency, prolonged or lifelong imaging surveillance is recommended after definitive surgery. (keeney1989adamantinomaoflong pages 1-2, amr2026managementoftibial pages 6-7, amr2026managementoftibial pages 8-9) NCIT: Surveillance, Follow-Up Care
Evidence gaps No robust evidence for infectious cause, environmental cause, protective factors, gene-environment interaction, validated circulating biomarkers, disease-specific staging system, standard targeted therapy, immunotherapy, liquid biopsy, single-cell or spatial transcriptomics atlas, animal model, or natural nonhuman disease counterpart was established in the retrieved evidence. Clinical-trial search did not identify relevant interventional trials for this disease; false-positive hits referred to ameloblastoma/craniopharyngioma. (OpenTargets Search: adamantinoma, wegrzyniak2023currentclinicopathologicalcharacterisation pages 1-5, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9, wegrzyniak2023currentclinicopathologicalcharacterisation pages 9-13) Evidence gap annotation; NCIT: Not Available / Unknown

Table: This compact table summarizes the most evidence-supported knowledge-base fields for adamantinoma of long bones, emphasizing distinctions among classic, OFD-like, and adamantinoma-like Ewing entities. It is useful for rapid curation because it combines clinical facts, molecular caveats, and suggested ontology mappings in one place.

1. Disease information

Definition and classification

Adamantinoma is an exceedingly rare, primary, usually low-grade malignant bone neoplasm characterized by epithelial tumor cells embedded in an osteofibrous or fibroblastic stroma. Its canonical location is the anterior cortex and diaphysis of the tibia. The 2020 WHO classification uses the name “adamantinoma of long bones”, places it among “other mesenchymal tumours of bone,” and recognizes classic, osteofibrous-dysplasia-like (OFD-like), and dedifferentiated forms. OFD-like adamantinoma is classified as intermediate/locally aggressive, whereas classic and dedifferentiated forms are malignant. The 2008 review’s abstract states directly: “Adamantinoma is a primary low-grade, malignant bone tumor that is predominantly located in the mid-portion of the tibia.” (jain2008adamantinomaaclinicopathological pages 1-2, wegrzyniak2023currentclinicopathologicalcharacterisation pages 1-5, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9)

Identifiers and synonyms

  • MONDO: MONDO:0002422, adamantinoma. Open Targets returned this disease record but no established associated therapeutic target. (OpenTargets Search: adamantinoma)
  • Common names: adamantinoma; adamantinoma of long bones; long-bone adamantinoma; tibial adamantinoma.
  • Subtype synonyms: differentiated adamantinoma, juvenile adamantinoma, intracortical adamantinoma, regressive adamantinoma, and OFD-like adamantinoma have historically overlapped, although current WHO terminology favors OFD-like adamantinoma.
  • MeSH: Adamantinoma is an indexed disease concept; curators should verify the current identifier in the target terminology release.
  • ICD: There is no sufficiently specific ICD-10-CM code for adamantinoma. Coding generally uses the malignant bone-neoplasm code selected by anatomical site; ICD-O morphology coding should be checked against the applicable registry edition.
  • OMIM/Orphanet: No hereditary Mendelian disease entry or causal-gene record was established in the retrieved evidence. A specific Orphanet identifier should not be asserted without direct registry verification.

The evidence summarized here is aggregated disease-level literature, not individual EHR-derived data. The 2024 report is an individual clinical case and is identified as such. (monteiro2024adamantinomadetíbia pages 1-4, monteiro2024adamantinomadetíbia pages 4-6)

2. Etiology and risk factors

The cause remains unknown. Epithelial differentiation is strongly supported by broad cytokeratin staining and ultrastructural features including basal lamina and desmosomes. Historical hypotheses—embryonic displacement of basal epidermal cells, traumatic implantation, synovial, vascular, or mesenchymal origin—have not yielded a proven initiating cause. The embryonic-displacement hypothesis was motivated by the tumor’s anterior tibial predilection, where skin lies close to developing bone. (jain2008adamantinomaaclinicopathological pages 1-2)

Risk, protective, and gene–environment factors

  • Germline risk: No validated causal germline variant, susceptibility locus, familial syndrome, founder mutation, carrier state, or Mendelian inheritance pattern is established.
  • Age/sex: Typical presentation is in the second through fifth decades, especially ages 20–40. A slight male excess is repeatedly reported. These are demographic associations, not demonstrated causal factors. (keeney1989adamantinomaoflong pages 1-2, jain2008adamantinomaaclinicopathological pages 1-2, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9)
  • Trauma: Trauma has often been reported, but evidence is inconsistent. In the 85-case series, only 12 patients had a trauma history and the authors could not infer causality; an older literature review reported trauma in approximately 60%. Trauma may simply draw attention to a pre-existing lesion. (keeney1989adamantinomaoflong pages 1-2, keeney1989adamantinomaoflong pages 2-3, keeney1989adamantinomaoflong pages 6-7, jain2008adamantinomaaclinicopathological pages 1-2)
  • Environmental/lifestyle/occupational exposures: No reproducible association with smoking, alcohol, diet, radiation, toxins, pollution, occupation, or physical inactivity is established.
  • Infection: No bacterial, viral, fungal, or parasitic cause is known.
  • Protective factors and gene–environment interactions: None validated.

3. Phenotypes

Presentation is typically insidious, chronic, and progressive. In the 85-case series, among 65 patients with known symptoms, 34 had pain plus swelling, 14 painless swelling, 14 pain alone, and three pathological fracture. Symptom duration ranged from two weeks to 50 years; 41/64 patients had symptoms for less than five years and 23 for at least five years. (keeney1989adamantinomaoflong pages 1-2)

Phenotype Type and characteristics Suggested HPO term
Localized limb/bone pain Common symptom; variable severity; chronic progressive course HP:0012531 Pain; more specific bone-pain term if available
Local swelling/mass Common clinical sign; usually firm, sometimes warm HP:0009826 Limb swelling
Progressive tibial deformity/bowing Less frequent; reflects anterior cortical remodeling HP:0000927 Abnormality of the skeletal system; tibial bowing term where supported
Pathological fracture Reported in approximately 10% radiographically in the 85-case study and up to 23% in reviews HP:0002757 Pathological fracture
Stiffness/impaired weight-bearing Functional manifestation in larger lesions HP:0001382 Joint stiffness, gait-abnormality term if documented
Osteolytic lesion Imaging phenotype, often multilocular with peripheral sclerosis HP:0031837 Osteolytic lesion
Neurologic deficit Rare, restricted to spinal disease Site-specific neurologic HPO term
Hypercalcemia Very rare paraneoplastic finding reported with pulmonary metastases HP:0003072 Hypercalcemia

There are no robust disease-specific EQ-5D, SF-36, PROMIS, or utility estimates. Quality of life may be impaired by pain, reduced weight-bearing, deformity, fracture, major resection, graft or prosthetic complications, limb-length discrepancy, repeated reconstruction, or amputation. The 2024 pediatric case explicitly reported limitation of daily activities. (monteiro2024adamantinomadetíbia pages 4-6)

4. Genetic and molecular information

Tumor genetics

Adamantinoma is not presently a hereditary single-gene disorder. Reported abnormalities are tumor-level/somatic research findings, not clinically validated constitutional pathogenic variants.

  • Aneuploidy and recurrent extra copies of chromosomes 7, 8, 12, 19, and 21 have been reported. (jain2008adamantinomaaclinicopathological pages 6-8, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9)
  • A 2019 molecular study summarized by the 2023 review proposed KMT2D mutation and increased DLK1 expression as potential markers. These are candidate findings—not sufficient to define a causal gene, ACMG pathogenic germline variant, or approved treatment target. (wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9)
  • Open Targets listed zero established target associations for MONDO:0002422. This is important negative evidence against importing BRAF/SMO findings from ameloblastoma or CTNNB1 findings from adamantinomatous craniopharyngioma. (OpenTargets Search: adamantinoma)
  • No validated modifier gene, allele frequency, penetrance estimate, pharmacogenomic marker, or standard ClinVar-classified disease variant is established.

Protein and immunophenotypic findings

The epithelial tumor cells express broad cytokeratins, particularly KRT5, KRT14, and KRT19, and commonly p63; EMA is often reported but may be variable. Older studies found p53 immunoreactivity in epithelial cells. The osteofibrous stroma is vimentin-positive. Keratin expression and epithelial ultrastructure support true epithelial differentiation. (amr2026managementoftibial pages 4-6, jain2008adamantinomaaclinicopathological pages 1-2, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9)

A 2024 classic-tumor case was AE1/AE3-positive in the epithelial component and p63-positive, but EMA, CK19, CD34, and the reported CK99 stain were negative, illustrating that a panel plus morphology is more reliable than any single marker. (monteiro2024adamantinomadetíbia pages 4-6)

Epigenetics and structural abnormalities

No reproducible disease-defining methylation class, histone-mark signature, enhancer alteration, or chromosomal translocation is established for true adamantinoma. This differs critically from ALES, which usually has a FET–ETS fusion such as EWSR1::FLI1. Molecular testing is particularly appropriate in a small-round-cell, head-and-neck, or otherwise atypical “adamantinoma-like” lesion. (rekhi2025osteofibrousdysplasia(ofd) pages 8-10)

5. Environmental information

No causal toxin, radiation exposure, pollutant, occupational exposure, lifestyle behavior, or infectious agent has been demonstrated. Trauma is best treated as an uncertain historical association rather than an environmental cause. Consequently, there are no evidence-based dietary, exercise, exposure-avoidance, antimicrobial, or vaccination recommendations specific to disease prevention.

6. Mechanism and pathophysiology

Current causal model

  1. An unidentified initiating event produces an epithelial neoplastic clone in cortical bone.
  2. Tumor epithelial cells proliferate as nests, cords, tubules, basaloid islands, squamous areas, or spindle-shaped cells.
  3. Epithelial–stromal signaling promotes a prominent fibro-osseous response, yielding the characteristic biphasic lesion.
  4. Slow longitudinal growth causes cortical osteolysis, sclerosis, expansion, medullary extension, deformity, pain, and sometimes fracture.
  5. Cortical breakthrough permits soft-tissue extension; lymphovascular dissemination produces regional-node and pulmonary metastases.
  6. In rare cases, dedifferentiation generates a high-grade pleomorphic sarcomatous component and more aggressive behavior. (jain2008adamantinomaaclinicopathological pages 2-4, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9, wegrzyniak2023currentclinicopathologicalcharacterisation pages 9-13)

The epithelial component has greater Ki-67 and growth-factor/receptor expression than the stroma in older studies, supporting the interpretation that epithelial cells are the neoplastic driver and that osteofibrous tissue is at least partly reactive. Nevertheless, whether OFD, OFD-like adamantinoma, and classic adamantinoma form a universal biological continuum remains disputed. Documented progression supports a continuum in some patients, but older clinicopathologic work did not establish that ordinary OFD is invariably a precursor. (jain2008adamantinomaaclinicopathological pages 4-5, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9)

Suggested annotations include GO epithelial cell proliferation, GO extracellular matrix organization, GO cell population proliferation, and GO epithelial cell differentiation; cell types include CL epithelial cell and CL fibroblast. There is no established disease-specific metabolic, autophagic, immune-checkpoint, inflammatory, mitochondrial, or ion-channel mechanism.

Molecular profiling and advanced technologies

Small genomic/cytogenetic studies exist, but no validated transcriptomic classifier, clinical proteomic or metabolomic signature, lipidomic profile, single-cell atlas, spatial-transcriptomic map, integrated multi-omics cohort, or CRISPR/RNAi dependency screen was identified. These are major research gaps.

7. Anatomical structures affected

  • Primary organ/system: skeleton, especially long bones of the lower limb.
  • Canonical site: anterior cortex of the tibial diaphysis; suggested terms: UBERON tibia, UBERON cortical bone, UBERON diaphysis.
  • Secondary local structures: medullary cavity/bone marrow, periosteum, adjacent fibula, subcutaneous tissue, and other soft tissues.
  • Frequency: Reviews estimate 97% occur in long bones and 80–85% in the tibia. In the primary 85-case series, 70/85 involved the tibia; 11 of those also involved the fibula. Six arose in femur, three ulna, two humerus, two fibula, one radius, and one pretibial soft tissue. Approximately 90% were diaphyseal. (keeney1989adamantinomaoflong pages 1-2, keeney1989adamantinomaoflong pages 2-3, jain2008adamantinomaaclinicopathological pages 1-2)
  • Distant sites: lung and regional lymph nodes predominate; bone, vertebral column, brain, and other sites are rare.
  • Lateralization: no meaningful biological laterality is established; the 85-case series had 34 right and 32 left lesions among cases with known side. (keeney1989adamantinomaoflong pages 2-3)
  • Subcellular compartments: diagnostic keratins are cytoplasmic/cytoskeletal; p63/p53 are nuclear. No organelle-specific pathogenic defect is known.

8. Temporal development

Classic adamantinoma most often presents from adolescence through middle adulthood, with a median/typical age around 25–35 years; OFD-like disease is enriched in children and adolescents, generally under 20. The 85-case series had an age range of 3–72 years and mean age 25.9 years. (keeney1989adamantinomaoflong pages 1-2, jain2008adamantinomaaclinicopathological pages 1-2, jain2008adamantinomaaclinicopathological pages 2-4)

The course is chronic and slowly progressive rather than episodic. Local recurrence in the 85-case series occurred after a mean 4.7 years, range 3 months–19.4 years; lymph-node metastasis occurred after a mean 5.8 years, and lung metastasis after a mean 8.2 years, range 1.1–17.9 years. Events several decades after treatment have also been reported, supporting prolonged—often lifelong—surveillance. Spontaneous remission is not expected for classic adamantinoma; apparent regression is discussed principally in OFD/OFD-like lesions. (amr2026managementoftibial pages 6-7, keeney1989adamantinomaoflong pages 3-6)

9. Inheritance and population

Adamantinoma is sporadic, with no established autosomal dominant, autosomal recessive, X-linked, mitochondrial, polygenic, or anticipation pattern. Penetrance, carrier frequency, germline mosaicism, founder effects, consanguinity, and prenatal risk are therefore not applicable.

It accounts for approximately 0.1–0.5% of primary bone tumors, but reliable population incidence and point-prevalence estimates per 100,000 are not well established. No consistent ethnic, geographic, or endemic pattern is known. The 85-case cohort included 45 males, 39 females, and one patient of unknown sex; reviews summarize the sex ratio as approximately 5:4 male:female. (keeney1989adamantinomaoflong pages 1-2, jain2008adamantinomaaclinicopathological pages 1-2, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9)

10. Diagnostics

Recommended work-up

  1. Plain radiography: typically central or eccentric, longitudinal, multilocular osteolysis with septation, peripheral sclerosis, cortical expansion/thinning, and a “soap-bubble” appearance.
  2. MRI of the entire involved bone: best for skip/satellite foci, medullary extent, cortical breakthrough, soft-tissue involvement, and surgical margins. Typical signal is low/intermediate on T1 and high on T2/STIR, with enhancement. Two patterns are described: a solitary lobulated focus or multiple small nodules in one or more foci.
  3. CT: clarifies cortical destruction and mineralization; chest CT is important for pulmonary staging.
  4. Biopsy planned with the definitive sarcoma surgeon: central and extensive sampling is crucial because peripheral OFD-like areas may lack obvious epithelial nests.
  5. Histology and IHC: establish biphasic architecture and epithelial differentiation.
  6. Molecular testing where morphology is atypical: fusion testing helps exclude ALES and synovial sarcoma. (monteiro2024adamantinomadetíbia pages 4-6, jain2008adamantinomaaclinicopathological pages 2-4, jain2008adamantinomaaclinicopathological pages 9-10, wegrzyniak2023currentclinicopathologicalcharacterisation pages 9-13)

Pathology

Classic tumors contain bland epithelial nests within fibrous stroma. Patterns include tubular, basaloid, squamous, spindle-cell, and OFD-like forms. Mitoses are usually sparse—historically 0–2 per 10 high-power fields—and marked atypia is unusual outside dedifferentiated disease. OFD-like tumors are predominantly fibro-osseous and may contain only tiny keratin-positive epithelial clusters. (keeney1989adamantinomaoflong pages 2-3, jain2008adamantinomaaclinicopathological pages 2-4, wegrzyniak2023currentclinicopathologicalcharacterisation pages 9-13)

Differential diagnosis

The principal differentials are OFD, fibrous dysplasia, OFD-like adamantinoma, osteosarcoma, Ewing/ALES, intraosseous synovial sarcoma, metastatic carcinoma, epithelioid vascular tumors, nonossifying fibroma, and osteomyelitis. OFD is generally benign and strictly intracortical; true adamantinoma more often extends toward marrow and contains demonstrable epithelial tumor cells. ALES commonly arises in head/neck soft tissue or bone, expresses CD99/NKX2.2 and keratins, and is defined by a FET–ETS fusion. (rekhi2025osteofibrousdysplasia(ofd) pages 8-10, jain2008adamantinomaaclinicopathological pages 2-4, jain2008adamantinomaaclinicopathological pages 8-9)

No diagnostic blood/urine test, circulating biomarker, liquid biopsy, validated WES/WGS panel, CMA, mitochondrial assay, or repeat-expansion test is recommended routinely. There is no population screening or cascade testing.

11. Outcome and prognosis

In the 85-case primary series, 26/85 (31%) developed local recurrence, 13/85 (15%) lung metastases, 6/85 (7%) lymph-node metastases, and 11 died from disease. Nine of 13 patients with lung metastasis had preceding local recurrence, and recurrence significantly increased pulmonary-metastasis risk. (keeney1989adamantinomaoflong pages 1-2, keeney1989adamantinomaoflong pages 3-6, keeney1989adamantinomaoflong pages 6-7)

Broader reviews report local recurrence around 18–32%, metastasis approximately 12–30%, and mortality around 13–18%, but these estimates mix eras and treatments. A modern synthesis cited 5- and 10-year recurrence estimates of 8.6% and 18.6%, 10-year disease-specific survival of 92%, and recurrence-free survival of 72%; interpretation requires caution because source populations and subtype composition differ. (jain2008adamantinomaaclinicopathological pages 6-8, amr2026managementoftibial pages 6-7, amr2026managementoftibial pages 8-9, kumar2021anunusualcase pages 6-7)

Adverse factors reported across retrospective studies include inadequate/intralesional surgery or positive margins, male sex, pain, symptom duration under five years, local recurrence, pathological fracture, skip lesions/periosteal involvement, younger age, and absence of squamous differentiation. Margin status is the most actionable and consistent factor. These associations should not be treated as validated individual-risk calculators. (jain2008adamantinomaaclinicopathological pages 6-8, amr2026managementoftibial pages 8-9, keeney1989adamantinomaoflong pages 1-2, keeney1989adamantinomaoflong pages 6-7)

12. Treatment

Standard treatment

Wide en-bloc resection with histologically negative margins is the treatment of choice. Limb salvage is preferred when adequate margins and useful function are achievable. Reconstruction may use intercalary allograft, vascularized fibular autograft, bone transport/distraction osteogenesis, endoprosthetic reconstruction, or combinations selected by tumor length, joint involvement, age, and remaining growth. Suggested NCIT terms include Surgical Resection, Wide Excision, Limb Salvage Procedure, Bone Grafting, Reconstructive Surgical Procedure, and Amputation. (jain2008adamantinomaaclinicopathological pages 6-8, amr2026managementoftibial pages 8-9, kumar2021anunusualcase pages 6-7, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9)

Amputation is reserved for unresectable or repeatedly recurrent disease, inability to obtain margins, major neurovascular involvement, infection, or failed reconstruction; it has not shown an inherent survival advantage over adequate wide resection. Curettage and other intralesional procedures are inappropriate for classic adamantinoma because of high recurrence risk. (amr2026managementoftibial pages 6-7, wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9)

Systemic and radiation treatment

Conventional chemotherapy and radiotherapy have no established routine efficacy. Anecdotal use of tyrosine-kinase inhibitors such as pazopanib or sunitinib has been discussed for unresectable/metastatic disease, but there is no validated response rate, approved adamantinoma-specific target, or standard regimen. Genotype-guided therapy, checkpoint inhibition, CAR-T therapy, gene therapy, ASOs/siRNA, and mRNA therapy are investigational or unsupported. (jain2008adamantinomaaclinicopathological pages 6-8, amr2026managementoftibial pages 8-9, kumar2021anunusualcase pages 6-7)

A ClinicalTrials.gov search did not identify a relevant adamantinoma interventional study; retrieved hits concerned similarly named ameloblastoma or craniopharyngioma and must not be assigned to this disease.

Supportive care

Management includes analgesia, fracture precautions, physical and occupational therapy, gait training, orthotics/prosthetics when appropriate, surveillance of graft union and hardware, and psychosocial support. Reconstruction can require repeated revision because of nonunion, graft fracture, infection, limb-length discrepancy, or prosthetic failure. No adamantinoma-specific pharmacogenomic guidance exists.

13. Prevention

There is no known primary prevention because no modifiable cause is established. There is no population, newborn, carrier, prenatal, or germline screening program and no vaccine or prophylactic drug.

Secondary prevention consists of prompt specialist assessment of persistent tibial pain, swelling, deformity, or a characteristic cortical lesion and avoiding unplanned curettage. Tertiary prevention includes complete initial resection, fracture prevention, rehabilitation, and very long-term local and chest surveillance. Genetic counseling is not routinely indicated for familial risk, although counseling about the absence of demonstrated heritability may be useful.

14. Other species and natural disease

No well-validated naturally occurring veterinary counterpart, breed predisposition, orthologous causal gene, cross-species susceptibility, or comparative spontaneous-disease cohort was identified. Adamantinoma is not infectious and has no zoonotic or cross-species transmission potential. Reports using “adamantinoma” in veterinary or older pathology sources require careful review because the term has historically been applied to odontogenic tumors.

15. Model organisms and experimental systems

No standardized mouse, rat, zebrafish, invertebrate, genetically engineered, humanized, patient-derived xenograft, organoid, iPSC, or validated cell-line model was identified. Consequently, no model has been shown to reproduce the human tibial cortical localization, biphasic epithelial–osteofibrous architecture, prolonged latency, or late metastatic behavior. Development of authenticated patient-derived cultures, organoids, xenografts, and spatial/single-cell datasets is a major unmet research need.

Recent developments and expert interpretation

The 2023 review emphasizes three practical developments: adoption of the 2020 WHO three-part classification, increasing use of combined immunohistochemical and genetic assessment, and MRI-based definition of full tumor extent before wide-margin surgery. Its abstract concludes that “confirmation of the immunohistochemical profile, as well as the genetic profile…is essential for diagnosis” and that the best treatment remains resection with large margins. (wegrzyniak2023currentclinicopathologicalcharacterisation pages 1-5)

The 2024 tibial case illustrates current real-world implementation: serial radiography, CT and MRI; centrally sampled biopsy; morphology plus p63/AE1-AE3 IHC; and limb-preserving resection/reconstruction. It also demonstrates the risk of misleading early imaging labels and postoperative functional complications in young patients. (monteiro2024adamantinomadetíbia pages 1-4, monteiro2024adamantinomadetíbia pages 4-6)

The central expert conclusion is that adamantinoma remains a surgically curable but deceptively persistent malignancy. Accurate subtype assignment, exclusion of molecular mimics, complete initial resection, and decades-long surveillance are more clinically consequential than presently available molecular-targeting strategies.

References

  1. (wegrzyniak2023currentclinicopathologicalcharacterisation pages 1-5): A Węgrzyniak, W Wokurka, and D Drobek. Current clinicopathological characterisation of adamantinoma-a review of the literature. Unknown journal, 2023.

  2. (wegrzyniak2023currentclinicopathologicalcharacterisation pages 5-9): A Węgrzyniak, W Wokurka, and D Drobek. Current clinicopathological characterisation of adamantinoma-a review of the literature. Unknown journal, 2023.

  3. (jain2008adamantinomaaclinicopathological pages 1-2): Deepali Jain, Vijay K Jain, Rakesh K Vasishta, Prabhat Ranjan, and Yashwant Kumar. Adamantinoma: a clinicopathological review and update. Diagnostic Pathology, 3:8-8, Feb 2008. URL: https://doi.org/10.1186/1746-1596-3-8, doi:10.1186/1746-1596-3-8. This article has 130 citations and is from a peer-reviewed journal.

  4. (rekhi2025osteofibrousdysplasia(ofd) pages 8-10): B Rekhi, R Jayan, R Jayan, and B Rekhi. Osteofibrous dysplasia (ofd) and adamantinoma: a comprehensive review and updates. Histology and histopathology, pages 18950, Jun 2025. URL: https://doi.org/10.14670/hh-18-950, doi:10.14670/hh-18-950. This article has 3 citations and is from a peer-reviewed journal.

  5. (keeney1989adamantinomaoflong pages 1-2): Gary L. Keeney, K. Krishnan Unni, John W. Beabout, and Douglas J. Pritchard. Adamantinoma of long bones. a clinicopathologic study of 85 cases. Cancer, 64:730-737, Aug 1989. URL: https://doi.org/10.1002/1097-0142(19890801)64:3<730::aid-cncr2820640327>3.0.co;2-p, doi:10.1002/1097-0142(19890801)64:3<730::aid-cncr2820640327>3.0.co;2-p. This article has 218 citations and is from a domain leading peer-reviewed journal.

  6. (jain2008adamantinomaaclinicopathological pages 2-4): Deepali Jain, Vijay K Jain, Rakesh K Vasishta, Prabhat Ranjan, and Yashwant Kumar. Adamantinoma: a clinicopathological review and update. Diagnostic Pathology, 3:8-8, Feb 2008. URL: https://doi.org/10.1186/1746-1596-3-8, doi:10.1186/1746-1596-3-8. This article has 130 citations and is from a peer-reviewed journal.

  7. (keeney1989adamantinomaoflong pages 2-3): Gary L. Keeney, K. Krishnan Unni, John W. Beabout, and Douglas J. Pritchard. Adamantinoma of long bones. a clinicopathologic study of 85 cases. Cancer, 64:730-737, Aug 1989. URL: https://doi.org/10.1002/1097-0142(19890801)64:3<730::aid-cncr2820640327>3.0.co;2-p, doi:10.1002/1097-0142(19890801)64:3<730::aid-cncr2820640327>3.0.co;2-p. This article has 218 citations and is from a domain leading peer-reviewed journal.

  8. (kumar2021anunusualcase pages 6-7): Arvind Kumar, Ruchi Sharma, Anil Kumar Verma, Abhijeet Tiwari, and Jyoti Mishra. An unusual case of adamantinoma of long bone. Autopsy & Case Reports, 11:e2021276, May 2021. URL: https://doi.org/10.4322/acr.2021.276, doi:10.4322/acr.2021.276. This article has 7 citations.

  9. (wegrzyniak2023currentclinicopathologicalcharacterisation pages 9-13): A Węgrzyniak, W Wokurka, and D Drobek. Current clinicopathological characterisation of adamantinoma-a review of the literature. Unknown journal, 2023.

  10. (jain2008adamantinomaaclinicopathological pages 6-8): Deepali Jain, Vijay K Jain, Rakesh K Vasishta, Prabhat Ranjan, and Yashwant Kumar. Adamantinoma: a clinicopathological review and update. Diagnostic Pathology, 3:8-8, Feb 2008. URL: https://doi.org/10.1186/1746-1596-3-8, doi:10.1186/1746-1596-3-8. This article has 130 citations and is from a peer-reviewed journal.

  11. (amr2026managementoftibial pages 4-6): Yasser Amr, Aye Htun, and Simerjit Singh. Management of tibial adamantinoma: balancing oncologic cure and reconstructive longevity. Cureus, Aug 2026. URL: https://doi.org/10.7759/cureus.113794, doi:10.7759/cureus.113794. This article has 0 citations.

  12. (jain2008adamantinomaaclinicopathological pages 4-5): Deepali Jain, Vijay K Jain, Rakesh K Vasishta, Prabhat Ranjan, and Yashwant Kumar. Adamantinoma: a clinicopathological review and update. Diagnostic Pathology, 3:8-8, Feb 2008. URL: https://doi.org/10.1186/1746-1596-3-8, doi:10.1186/1746-1596-3-8. This article has 130 citations and is from a peer-reviewed journal.

  13. (monteiro2024adamantinomadetíbia pages 4-6): LS de Sousa Monteiro and LF Vitule. Adamantinoma de tíbia: adamantinoma of the tibia. Unknown journal, 2024.

  14. (jain2008adamantinomaaclinicopathological pages 9-10): Deepali Jain, Vijay K Jain, Rakesh K Vasishta, Prabhat Ranjan, and Yashwant Kumar. Adamantinoma: a clinicopathological review and update. Diagnostic Pathology, 3:8-8, Feb 2008. URL: https://doi.org/10.1186/1746-1596-3-8, doi:10.1186/1746-1596-3-8. This article has 130 citations and is from a peer-reviewed journal.

  15. (jain2008adamantinomaaclinicopathological pages 8-9): Deepali Jain, Vijay K Jain, Rakesh K Vasishta, Prabhat Ranjan, and Yashwant Kumar. Adamantinoma: a clinicopathological review and update. Diagnostic Pathology, 3:8-8, Feb 2008. URL: https://doi.org/10.1186/1746-1596-3-8, doi:10.1186/1746-1596-3-8. This article has 130 citations and is from a peer-reviewed journal.

  16. (keeney1989adamantinomaoflong pages 6-7): Gary L. Keeney, K. Krishnan Unni, John W. Beabout, and Douglas J. Pritchard. Adamantinoma of long bones. a clinicopathologic study of 85 cases. Cancer, 64:730-737, Aug 1989. URL: https://doi.org/10.1002/1097-0142(19890801)64:3<730::aid-cncr2820640327>3.0.co;2-p, doi:10.1002/1097-0142(19890801)64:3<730::aid-cncr2820640327>3.0.co;2-p. This article has 218 citations and is from a domain leading peer-reviewed journal.

  17. (amr2026managementoftibial pages 6-7): Yasser Amr, Aye Htun, and Simerjit Singh. Management of tibial adamantinoma: balancing oncologic cure and reconstructive longevity. Cureus, Aug 2026. URL: https://doi.org/10.7759/cureus.113794, doi:10.7759/cureus.113794. This article has 0 citations.

  18. (amr2026managementoftibial pages 8-9): Yasser Amr, Aye Htun, and Simerjit Singh. Management of tibial adamantinoma: balancing oncologic cure and reconstructive longevity. Cureus, Aug 2026. URL: https://doi.org/10.7759/cureus.113794, doi:10.7759/cureus.113794. This article has 0 citations.

  19. (OpenTargets Search: adamantinoma): Open Targets Query (adamantinoma, 6 results). Buniello, A. et al. (2025). Open Targets Platform: facilitating therapeutic hypotheses building in drug discovery. Nucleic Acids Research.

  20. (monteiro2024adamantinomadetíbia pages 1-4): LS de Sousa Monteiro and LF Vitule. Adamantinoma de tíbia: adamantinoma of the tibia. Unknown journal, 2024.

  21. (keeney1989adamantinomaoflong pages 3-6): Gary L. Keeney, K. Krishnan Unni, John W. Beabout, and Douglas J. Pritchard. Adamantinoma of long bones. a clinicopathologic study of 85 cases. Cancer, 64:730-737, Aug 1989. URL: https://doi.org/10.1002/1097-0142(19890801)64:3<730::aid-cncr2820640327>3.0.co;2-p, doi:10.1002/1097-0142(19890801)64:3<730::aid-cncr2820640327>3.0.co;2-p. This article has 218 citations and is from a domain leading peer-reviewed journal.

Artifacts

Reference Validation

Checked with linkml-reference-validator 0.2.1.

Outcome Count
References checked 8
Resolved 5
Unresolved (possible confabulation) 1
Unverifiable 2
References weighed for topical relevance 5
On topic 1
Off topic 0

Unresolved references

These identifiers did not resolve to a record and may be fabricated. A lookup that failed for transport reasons is indistinguishable from one that failed because the record does not exist, so spot-check before acting on them:

  • DOI:10.14670/hh-18-950 (3 mentions) - Identifier did not resolve to a record