◆

Subtypes

3

Pleural/Thoracic Solitary Fibrous Tumor

The classic and most common presentation, arising from the visceral or parietal pleura. Frequently asymptomatic and discovered incidentally, larger lesions cause cough, dyspnea, or chest pain. Most are benign with a NAB2-STAT6 fusion; complete surgical resection is usually curative. Pleural SFTs may present with paraneoplastic hypoglycemia (Doege-Potter syndrome).

Extrapleural / Meningeal Solitary Fibrous Tumor

SFT arising outside the pleura, including the meninges/central nervous system (formerly hemangiopericytoma), abdomen, pelvis, retroperitoneum, head and neck, and extremities. Meningeal/intracranial SFTs share the NAB2-STAT6 fusion and are graded by the WHO CNS classification; they carry a notable risk of local recurrence and metastasis and often require postoperative radiotherapy.

Malignant / Dedifferentiated Solitary Fibrous Tumor

A higher-grade form defined by high mitotic activity, large size, necrosis, and/or hypercellularity, frequently with additional TP53 and TERT-promoter alterations and loss of APAF1. Dedifferentiated SFT shows abrupt transition to a high-grade, often anaplastic sarcoma and behaves aggressively with high rates of metastasis. Antiangiogenic therapy is favored for advanced non-dedifferentiated disease.

Show evidence (1 reference)

PMID:31321477 SUPPORT Human Clinical

"a TERT promoter mutation was detected in 7/73 (10%) cases, and it showed a significant association with malignant SFTs"

Supports the definition of malignant SFT as a molecularly distinct, higher-risk subtype enriched for TERT-promoter mutations.

⚙

Pathophysiology

6

NAB2-STAT6 Fusion Oncogene

A recurrent intrachromosomal rearrangement on chromosome 12q13 fuses the NAB2 gene to STAT6. NAB2-STAT6 is the defining molecular feature of SFT, identified by whole-exome sequencing across the SFT spectrum (including tumors formerly called hemangiopericytoma). The chimeric product joins the truncated repressor domain of NAB2 to the intact transactivation domain of STAT6.

fibroblast CL:0000057

Downstream

Aberrant EGR1-Target Transactivation The chimeric protein converts NAB2's repressor function into an EGR1-target transcriptional activator.

Show evidence (1 reference)

PMID:23313954 SUPPORT Human Clinical

"Analysis in 53 tumors confirmed the presence of 7 variants of this fusion transcript in 29 tumors (55%), representing a lower bound for fusion frequency at this locus and suggesting that the NAB2-STAT6 fusion is a distinct molecular feature of SFTs."

Landmark whole-exome sequencing study establishing the recurrent NAB2-STAT6 fusion as the defining driver of solitary fibrous tumor.

Aberrant EGR1-Target Transactivation

Native NAB2 represses EGR1 (EGR-1) target genes. The NAB2-STAT6 fusion replaces the NAB2 repressor activity with the STAT6 transactivation domain, so EGR1-target genes are aberrantly activated. STAT6 accumulates in the nucleus (the basis of the diagnostic nuclear STAT6 immunostain). Upregulation of EGR1 and its proliferation- associated target IGF2 drives p-Rb/cyclin D1 and enhanced proliferation.

regulation of DNA-templated transcription GO:0006355 ↑ INCREASED positive regulation of transcription by RNA polymerase II GO:0045944 ↑ INCREASED

Downstream

Fibroblastic Proliferation EGR1/IGF2-driven cell-cycle entry (p-Rb, cyclin D1) sustains tumor-cell proliferation.

Paraneoplastic Big-IGF-II Secretion (Doege-Potter Syndrome) EGR1-driven IGF2 upregulation downstream of NAB2-STAT6 provides the mechanistic basis for Big-IGF-II overproduction in a subset of SFTs.

Show evidence (1 reference)

PMID:32216968 SUPPORT In Vitro

"we found that EGR-1 and the proliferation-related EGR-1 target gene IGF2 were upregulated in NIH-3T3 cells transfected with NAB2-STAT6."

In vitro evidence that the NAB2-STAT6 fusion aberrantly activates EGR-1 and its target IGF2, the mechanistic basis for fibroblastic proliferation in SFT.

Fibroblastic Proliferation

Aberrant EGR1/IGF2 signaling drives p-Rb (Ser795) and cyclin D1 upregulation and enhanced proliferation of the spindled fibroblastic tumor cells, producing the patternless, variably cellular architecture of SFT with branching "staghorn" thin-walled vasculature.

fibroblast CL:0000057

cell population proliferation GO:0008283 ↑ INCREASED angiogenesis GO:0001525

Downstream

Malignant Transformation via TP53/TERT A subset of established SFTs acquire additional TERT-promoter and TP53 alterations with APAF1 loss, driving malignant transformation and dedifferentiation on the background of the proliferating tumor.

Show evidence (1 reference)

PMID:32216968 SUPPORT In Vitro

"p-Rb (Ser795) and cyclin D1 levels were upregulated, and cell proliferation was also enhanced."

Demonstrates that NAB2-STAT6 expression drives cell-cycle progression and proliferation of fibroblastic cells.

Paraneoplastic Big-IGF-II Secretion (Doege-Potter Syndrome)

A subset of SFTs secretes incompletely processed insulin-like growth factor II ("Big-IGF-II"), a precursor of IGF-II. This prohormone aberrantly activates insulin/IGF receptors, inhibiting gluconeogenesis and stimulating glucose uptake, producing recurrent non-islet-cell tumor hypoglycemia known as Doege-Potter syndrome. EGR1-driven IGF2 upregulation downstream of NAB2-STAT6 provides a mechanistic link to the tumor's IGF-II production.

insulin-like growth factor receptor signaling pathway GO:0048009 ↑ INCREASED gluconeogenesis GO:0006094 ↓ DECREASED

Downstream

Tumor-Induced Hypoglycemia Big-IGF-II suppresses gluconeogenesis and increases glucose uptake.

Show evidence (1 reference)

PMID:38441351 SUPPORT Human Clinical

"Hypoglycemia can be attributed to paraneoplastic secretion of "Big-IGF-II," a precursor of Insulin-like growth factor-II."

Establishes Big-IGF-II secretion as the mechanism of Doege-Potter syndrome in SFT.

Tumor-Induced Hypoglycemia

Big-IGF-II activation of insulin receptors inhibits gluconeogenesis, activates glycolysis, and stimulates cellular glucose uptake, culminating in recurrent tumor-induced hypoglycemic episodes that resolve with tumor resection.

gluconeogenesis GO:0006094 ↓ DECREASED

Show evidence (1 reference)

PMID:38441351 SUPPORT Human Clinical

"inhibition of gluconeogenesis, activation of glycolysis and stimulation of cellular glucose uptake culminating in recurrent tumor-induced hypoglycemic episodes."

Describes the metabolic mechanism producing paraneoplastic hypoglycemia in Doege-Potter syndrome.

Malignant Transformation via TP53/TERT

Progression to malignant SFT is associated with TERT-promoter mutations and acquired TP53 dysfunction (TP53 immunopositivity) together with loss of APAF1, impairing apoptosis and contributing to aggressive, metastasizing behavior and dedifferentiation.

apoptotic process GO:0006915 ↓ DECREASED cell population proliferation GO:0008283 ↑ INCREASED

Show evidence (1 reference)

PMID:31321477 SUPPORT Human Clinical

"Our study suggests that dysfunction of TP53 and APAF1 leads to impaired apoptotic function, and eventually contributes toward malignant SFT transformation."

Links TP53 and APAF1 dysfunction to impaired apoptosis driving malignant SFT transformation.

✶

Histopathology

2

Vascular Staghorn Configuration

Branching, thin-walled "staghorn" (hemangiopericytoma-like) vasculature is a characteristic architectural hallmark of SFT.

Spindle Cell Pattern

Patternless arrangement of bland spindled-to-ovoid fibroblastic cells with variable cellularity and interspersed collagen, typical of SFT.

⬡

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.

●

Phenotypes

3

Metabolism 1

Hypoglycemia Hypoglycemia HP:0001943

Temporal: RECURRENT

Show evidence (1 reference)

PMID:38441351 SUPPORT Human Clinical

"Doege-Potter syndrome is defined as paraneoplastic hypoinsulinemic hypoglycemia associated with a benign or malignant solitary fibrous tumor frequently located in pleural, but also extrapleural sites."

Directly supports hypoglycemia as a paraneoplastic phenotype of SFT.

Respiratory 1

Dyspnea Dyspnea HP:0002094

Dyspnea, cough, and chest pain are well-recognized compressive symptoms of large pleural/thoracic SFTs, but no exact supporting snippet is available in the currently cached references; the available systemic-therapy reference (PMID:42149317) addresses treatment rather than respiratory symptoms, so the evidence block has been omitted pending a properly quotable source.

Neoplasm 1

Soft Tissue Mass Neoplasm HP:0002664

Show evidence (1 reference)

PMID:23313954 SUPPORT Human Clinical

"Solitary fibrous tumors (SFTs) are rare mesenchymal tumors."

Confirms SFT as a discrete mesenchymal neoplasm presenting as a mass.

🧬

Genetic Associations

2

NAB2-STAT6 fusion

Gene: STAT6 hgnc:11368 variant_origin: SOMATIC

Show evidence (1 reference)

PMID:23313954 SUPPORT Human Clinical

"Here, we describe the identification of a NAB2-STAT6 fusion from whole-exome sequencing of 17 SFTs."

Identifies the somatic NAB2-STAT6 fusion as the genetic basis of SFT.

NAB2 (NAB2-STAT6 fusion partner)

Gene: NAB2 hgnc:7627 variant_origin: SOMATIC

Show evidence (1 reference)

PMID:23313954 SUPPORT Human Clinical

"Here, we describe the identification of a NAB2-STAT6 fusion from whole-exome sequencing of 17 SFTs."

Identifies NAB2 as the 5' partner gene of the somatic SFT-defining fusion.

💊

Medical Actions

4

Surgical Resection

Action: surgical procedure MAXO:0000004

Complete surgical resection is the cornerstone of curative treatment for localized SFT; meningeal SFTs are managed by gross total or subtotal resection.

Show evidence (1 reference)

PMID:42149317 SUPPORT Human Clinical

"Complete surgical resection constitutes the cornerstone of treatment for localized disease"

Establishes surgery as the primary curative treatment for localized SFT.

Postoperative Radiotherapy

Action: radiation therapy MAXO:0000014

Adjuvant radiotherapy is used for meningeal/intracranial SFT after resection to reduce local recurrence, given the high recurrence risk of these tumors.

Show evidence (1 reference)

PMID:40354004 SUPPORT Human Clinical

"Postoperative radiotherapy (PORT) whether gross total resection (GTR) or subtotal resection (STR) may be the optimal treatment strategy"

Supports adjuvant radiotherapy after resection of meningeal malignant SFT.

Antiangiogenic Therapy

Action: Pharmacotherapy NCIT:C15986

Agent: pazopanib CHEBI:71219

Antiangiogenic tyrosine kinase inhibitors (e.g., pazopanib) are the standard systemic backbone for locally advanced or metastatic non-dedifferentiated SFT.

Mechanism Target:

INHIBITS Fibroblastic Proliferation — Antiangiogenic tyrosine kinase inhibitors target the tumor angiogenesis (GO:0001525) that supports the proliferating fibroblastic compartment.

Show evidence (1 reference)

PMID:42149317 SUPPORT Human Clinical

"Antiangiogenic agents have shown promising outcomes, particularly in non-dedifferentiated SFT, and are increasingly favored by some as first-line options."

Supports antiangiogenic therapy as the standard systemic backbone for advanced SFT.

Somatostatin Analogue Therapy

Action: Pharmacotherapy NCIT:C15986

Agent: octreotide CHEBI:7726

Somatostatin analogues (octreotide, lanreotide) can help control paraneoplastic hypoglycemia in Doege-Potter syndrome when complete resection is not feasible.

Mechanism Target:

INHIBITS Paraneoplastic Big-IGF-II Secretion (Doege-Potter Syndrome) — Somatostatin analogues suppress tumor secretion of Big-IGF-II, mitigating the paraneoplastic driver of Doege-Potter hypoglycemia.

Show evidence (1 reference)

PMID:38441351 SUPPORT Human Clinical

"The somatostatin-analogue Lanreotide was successfully used after tumor debulking surgery (R2-resection) to maintain adequate blood glucose control."

Supports somatostatin analogues for controlling Doege-Potter hypoglycemia when resection is incomplete.

🔬

Biochemical Markers

3

Nuclear STAT6 Expression

Show evidence (1 reference)

PMID:26722515 SUPPORT Human Clinical

"Nuclear STAT6 positive staining was present in 51 cases (51/53, sensitivity 96.2%)"

Demonstrates high sensitivity of nuclear STAT6 immunostaining for diagnosing SFT.

CD34 Expression

Show evidence (1 reference)

PMID:26722515 SUPPORT Human Clinical

"CD34 was positive in 47 cases (47/53, sensitivity 88.7%)"

Supports CD34 positivity as a characteristic SFT immunophenotype.

Big-IGF-II

{ }

Source YAML

click to show

name: Solitary Fibrous Tumor
creation_date: '2026-06-08T00:00:00Z'
description: >-
  Solitary fibrous tumor (SFT) is a rare fibroblastic mesenchymal neoplasm
  defined by a recurrent intrachromosomal NAB2-STAT6 gene fusion. The fusion
  converts the NAB2 transcriptional repressor into an aberrant EGR1-target
  transcriptional activator, driving constitutive STAT6 nuclear accumulation and
  fibroblastic proliferation. SFT encompasses tumors formerly termed
  hemangiopericytoma and characteristically displays a patternless architecture
  with branching, "staghorn" thin-walled vasculature, CD34 positivity, and
  diffuse nuclear STAT6 immunoreactivity. Most tumors are slow-growing and
  arise in the pleura, but extrapleural sites (meninges, abdomen, pelvis,
  extremities, head and neck) are common. Clinical behavior ranges from benign
  to malignant; risk of recurrence and metastasis is stratified using patient
  age, tumor size, mitotic index, and necrosis. A subset secretes "Big-IGF-II"
  causing paraneoplastic hypoglycemia (Doege-Potter syndrome). Malignant and
  dedifferentiated SFT carry additional TP53/TERT-promoter alterations and behave
  aggressively. Complete surgical resection is the mainstay of cure; antiangiogenic
  agents are the standard systemic backbone for advanced disease.
categories:
- Sarcoma
- Rare Cancer
parents:
- mesenchymal cell neoplasm
disease_term:
  preferred_term: solitary fibrous tumor
  term:
    id: MONDO:0016238
    label: solitary fibrous tumor
has_subtypes:
- name: Pleural SFT
  display_name: Pleural/Thoracic Solitary Fibrous Tumor
  description: >-
    The classic and most common presentation, arising from the visceral or
    parietal pleura. Frequently asymptomatic and discovered incidentally, larger
    lesions cause cough, dyspnea, or chest pain. Most are benign with a NAB2-STAT6
    fusion; complete surgical resection is usually curative. Pleural SFTs may
    present with paraneoplastic hypoglycemia (Doege-Potter syndrome).
- name: Extrapleural SFT
  display_name: Extrapleural / Meningeal Solitary Fibrous Tumor
  description: >-
    SFT arising outside the pleura, including the meninges/central nervous system
    (formerly hemangiopericytoma), abdomen, pelvis, retroperitoneum, head and neck,
    and extremities. Meningeal/intracranial SFTs share the NAB2-STAT6 fusion and
    are graded by the WHO CNS classification; they carry a notable risk of local
    recurrence and metastasis and often require postoperative radiotherapy.
- name: Malignant SFT
  display_name: Malignant / Dedifferentiated Solitary Fibrous Tumor
  description: >-
    A higher-grade form defined by high mitotic activity, large size, necrosis,
    and/or hypercellularity, frequently with additional TP53 and TERT-promoter
    alterations and loss of APAF1. Dedifferentiated SFT shows abrupt transition to
    a high-grade, often anaplastic sarcoma and behaves aggressively with high rates
    of metastasis. Antiangiogenic therapy is favored for advanced non-dedifferentiated
    disease.
  evidence:
  - reference: PMID:31321477
    reference_title: "Molecular changes in solitary fibrous tumor progression."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      a TERT promoter mutation was detected in 7/73 (10%) cases, and it showed a
      significant association with malignant SFTs
    explanation: >-
      Supports the definition of malignant SFT as a molecularly distinct,
      higher-risk subtype enriched for TERT-promoter mutations.
pathophysiology:
- name: NAB2-STAT6 Fusion Oncogene
  description: >-
    A recurrent intrachromosomal rearrangement on chromosome 12q13 fuses the NAB2
    gene to STAT6. NAB2-STAT6 is the defining molecular feature of SFT, identified
    by whole-exome sequencing across the SFT spectrum (including tumors formerly
    called hemangiopericytoma). The chimeric product joins the truncated repressor
    domain of NAB2 to the intact transactivation domain of STAT6.
  cell_types:
  - preferred_term: fibroblast
    term:
      id: CL:0000057
      label: fibroblast
  gene_products:
  - preferred_term: NAB2-STAT6 fusion protein
    term:
      id: NCIT:C122820
      label: NAB2/STAT6 Fusion Protein
  evidence:
  - reference: PMID:23313954
    reference_title: "Whole-exome sequencing identifies a recurrent NAB2-STAT6 fusion in solitary fibrous tumors."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Analysis in 53 tumors confirmed the presence of 7 variants of this fusion
      transcript in 29 tumors (55%), representing a lower bound for fusion
      frequency at this locus and suggesting that the NAB2-STAT6 fusion is a
      distinct molecular feature of SFTs.
    explanation: >-
      Landmark whole-exome sequencing study establishing the recurrent NAB2-STAT6
      fusion as the defining driver of solitary fibrous tumor.
  downstream:
  - target: Aberrant EGR1-Target Transactivation
    description: >-
      The chimeric protein converts NAB2's repressor function into an EGR1-target
      transcriptional activator.
- name: Aberrant EGR1-Target Transactivation
  description: >-
    Native NAB2 represses EGR1 (EGR-1) target genes. The NAB2-STAT6 fusion replaces
    the NAB2 repressor activity with the STAT6 transactivation domain, so EGR1-target
    genes are aberrantly activated. STAT6 accumulates in the nucleus (the basis of the
    diagnostic nuclear STAT6 immunostain). Upregulation of EGR1 and its proliferation-
    associated target IGF2 drives p-Rb/cyclin D1 and enhanced proliferation.
  biological_processes:
  - preferred_term: regulation of DNA-templated transcription
    modifier: INCREASED
    term:
      id: GO:0006355
      label: regulation of DNA-templated transcription
  - preferred_term: positive regulation of transcription by RNA polymerase II
    modifier: INCREASED
    term:
      id: GO:0045944
      label: positive regulation of transcription by RNA polymerase II
  gene_products:
  - preferred_term: Signal Transducer and Activator of Transcription 6
    term:
      id: NCIT:C28670
      label: Signal Transducer and Activator of Transcription 6
  evidence:
  - reference: PMID:32216968
    reference_title: "NAB2-STAT6 fusion protein mediates cell proliferation and oncogenic progression via EGR-1 regulation."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: >-
      we found that EGR-1 and the proliferation-related EGR-1 target gene IGF2 were
      upregulated in NIH-3T3 cells transfected with NAB2-STAT6.
    explanation: >-
      In vitro evidence that the NAB2-STAT6 fusion aberrantly activates EGR-1 and its
      target IGF2, the mechanistic basis for fibroblastic proliferation in SFT.
  downstream:
  - target: Fibroblastic Proliferation
    description: >-
      EGR1/IGF2-driven cell-cycle entry (p-Rb, cyclin D1) sustains tumor-cell
      proliferation.
  - target: Paraneoplastic Big-IGF-II Secretion (Doege-Potter Syndrome)
    description: >-
      EGR1-driven IGF2 upregulation downstream of NAB2-STAT6 provides the
      mechanistic basis for Big-IGF-II overproduction in a subset of SFTs.
- name: Fibroblastic Proliferation
  description: >-
    Aberrant EGR1/IGF2 signaling drives p-Rb (Ser795) and cyclin D1 upregulation and
    enhanced proliferation of the spindled fibroblastic tumor cells, producing the
    patternless, variably cellular architecture of SFT with branching "staghorn"
    thin-walled vasculature.
  cell_types:
  - preferred_term: fibroblast
    term:
      id: CL:0000057
      label: fibroblast
  biological_processes:
  - preferred_term: cell population proliferation
    modifier: INCREASED
    term:
      id: GO:0008283
      label: cell population proliferation
  - preferred_term: angiogenesis
    term:
      id: GO:0001525
      label: angiogenesis
  evidence:
  - reference: PMID:32216968
    reference_title: "NAB2-STAT6 fusion protein mediates cell proliferation and oncogenic progression via EGR-1 regulation."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: >-
      p-Rb (Ser795) and cyclin D1 levels were upregulated, and cell proliferation was
      also enhanced.
    explanation: >-
      Demonstrates that NAB2-STAT6 expression drives cell-cycle progression and
      proliferation of fibroblastic cells.
  downstream:
  - target: Malignant Transformation via TP53/TERT
    description: >-
      A subset of established SFTs acquire additional TERT-promoter and TP53
      alterations with APAF1 loss, driving malignant transformation and
      dedifferentiation on the background of the proliferating tumor.
- name: Paraneoplastic Big-IGF-II Secretion (Doege-Potter Syndrome)
  description: >-
    A subset of SFTs secretes incompletely processed insulin-like growth factor II
    ("Big-IGF-II"), a precursor of IGF-II. This prohormone aberrantly activates
    insulin/IGF receptors, inhibiting gluconeogenesis and stimulating glucose uptake,
    producing recurrent non-islet-cell tumor hypoglycemia known as Doege-Potter
    syndrome. EGR1-driven IGF2 upregulation downstream of NAB2-STAT6 provides a
    mechanistic link to the tumor's IGF-II production.
  biological_processes:
  - preferred_term: insulin-like growth factor receptor signaling pathway
    modifier: INCREASED
    term:
      id: GO:0048009
      label: insulin-like growth factor receptor signaling pathway
  - preferred_term: gluconeogenesis
    modifier: DECREASED
    term:
      id: GO:0006094
      label: gluconeogenesis
  gene_products:
  - preferred_term: Insulin-Like Growth Factor II
    term:
      id: NCIT:C16744
      label: Insulin-Like Growth Factor II
  evidence:
  - reference: PMID:38441351
    reference_title: "Effective management of recurrent Doege-Potter syndrome with somatostatin-analogues: A case report."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Hypoglycemia can be attributed to paraneoplastic secretion of "Big-IGF-II," a
      precursor of Insulin-like growth factor-II.
    explanation: >-
      Establishes Big-IGF-II secretion as the mechanism of Doege-Potter syndrome in SFT.
  downstream:
  - target: Tumor-Induced Hypoglycemia
    description: Big-IGF-II suppresses gluconeogenesis and increases glucose uptake.
- name: Tumor-Induced Hypoglycemia
  description: >-
    Big-IGF-II activation of insulin receptors inhibits gluconeogenesis, activates
    glycolysis, and stimulates cellular glucose uptake, culminating in recurrent
    tumor-induced hypoglycemic episodes that resolve with tumor resection.
  biological_processes:
  - preferred_term: gluconeogenesis
    modifier: DECREASED
    term:
      id: GO:0006094
      label: gluconeogenesis
  evidence:
  - reference: PMID:38441351
    reference_title: "Effective management of recurrent Doege-Potter syndrome with somatostatin-analogues: A case report."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      inhibition of gluconeogenesis, activation of glycolysis and stimulation of
      cellular glucose uptake culminating in recurrent tumor-induced hypoglycemic
      episodes.
    explanation: >-
      Describes the metabolic mechanism producing paraneoplastic hypoglycemia in
      Doege-Potter syndrome.
- name: Malignant Transformation via TP53/TERT
  description: >-
    Progression to malignant SFT is associated with TERT-promoter mutations and
    acquired TP53 dysfunction (TP53 immunopositivity) together with loss of APAF1,
    impairing apoptosis and contributing to aggressive, metastasizing behavior and
    dedifferentiation.
  biological_processes:
  - preferred_term: apoptotic process
    modifier: DECREASED
    term:
      id: GO:0006915
      label: apoptotic process
  - preferred_term: cell population proliferation
    modifier: INCREASED
    term:
      id: GO:0008283
      label: cell population proliferation
  evidence:
  - reference: PMID:31321477
    reference_title: "Molecular changes in solitary fibrous tumor progression."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Our study suggests that dysfunction of TP53 and APAF1 leads to impaired
      apoptotic function, and eventually contributes toward malignant SFT
      transformation.
    explanation: >-
      Links TP53 and APAF1 dysfunction to impaired apoptosis driving malignant SFT
      transformation.
phenotypes:
- category: Clinical
  name: Soft Tissue Mass
  description: >-
    SFT typically presents as a slow-growing, often painless mass; pleural lesions
    may be incidental, while large tumors cause local compressive symptoms.
  phenotype_term:
    preferred_term: Neoplasm
    term:
      id: HP:0002664
      label: Neoplasm
  evidence:
  - reference: PMID:23313954
    reference_title: "Whole-exome sequencing identifies a recurrent NAB2-STAT6 fusion in solitary fibrous tumors."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: Solitary fibrous tumors (SFTs) are rare mesenchymal tumors.
    explanation: Confirms SFT as a discrete mesenchymal neoplasm presenting as a mass.
- category: Clinical
  name: Hypoglycemia
  description: >-
    Paraneoplastic hypoinsulinemic hypoglycemia from Big-IGF-II secretion
    (Doege-Potter syndrome), occurring with pleural and extrapleural SFT.
  phenotype_term:
    preferred_term: Hypoglycemia
    term:
      id: HP:0001943
      label: Hypoglycemia
    temporality: RECURRENT
  evidence:
  - reference: PMID:38441351
    reference_title: "Effective management of recurrent Doege-Potter syndrome with somatostatin-analogues: A case report."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Doege-Potter syndrome is defined as paraneoplastic hypoinsulinemic
      hypoglycemia associated with a benign or malignant solitary fibrous tumor
      frequently located in pleural, but also extrapleural sites.
    explanation: Directly supports hypoglycemia as a paraneoplastic phenotype of SFT.
- category: Clinical
  name: Dyspnea
  description: >-
    Large pleural/thoracic SFTs compress lung parenchyma and airways, producing
    breathlessness, cough, and chest discomfort.
  subtype: Pleural SFT
  phenotype_term:
    preferred_term: Dyspnea
    term:
      id: HP:0002094
      label: Dyspnea
  notes: >-
    Dyspnea, cough, and chest pain are well-recognized compressive symptoms of
    large pleural/thoracic SFTs, but no exact supporting snippet is available in
    the currently cached references; the available systemic-therapy reference
    (PMID:42149317) addresses treatment rather than respiratory symptoms, so the
    evidence block has been omitted pending a properly quotable source.
histopathology:
- name: Vascular Staghorn Configuration
  finding_term:
    preferred_term: Vascular Staghorn Configuration
    term:
      id: NCIT:C35970
      label: Vascular Staghorn Configuration
  diagnostic: true
  description: >-
    Branching, thin-walled "staghorn" (hemangiopericytoma-like) vasculature is a
    characteristic architectural hallmark of SFT.
- name: Spindle Cell Pattern
  finding_term:
    preferred_term: Spindle Cell Pattern
    term:
      id: NCIT:C53643
      label: Spindle Cell Pattern
  description: >-
    Patternless arrangement of bland spindled-to-ovoid fibroblastic cells with
    variable cellularity and interspersed collagen, typical of SFT.
biochemical:
- name: Nuclear STAT6 Expression
  biomarker_term:
    preferred_term: Signal Transducer and Activator of Transcription 6
    term:
      id: NCIT:C28670
      label: Signal Transducer and Activator of Transcription 6
  notes: >-
    Diffuse nuclear STAT6 immunoreactivity is a highly sensitive and specific
    surrogate for the NAB2-STAT6 fusion and is the key diagnostic immunostain for SFT.
  evidence:
  - reference: PMID:26722515
    reference_title: "Immunohistochemical detection of STAT6, CD34, CD99 and BCL-2 for diagnosing solitary fibrous tumors/hemangiopericytomas."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Nuclear STAT6 positive staining was present in 51 cases (51/53, sensitivity
      96.2%)
    explanation: >-
      Demonstrates high sensitivity of nuclear STAT6 immunostaining for diagnosing SFT.
- name: CD34 Expression
  biomarker_term:
    preferred_term: Hematopoietic Progenitor Cell Antigen CD34
    term:
      id: NCIT:C17280
      label: Hematopoietic Progenitor Cell Antigen CD34
  notes: >-
    CD34 is positive in the majority of SFTs and, together with CD99 and Bcl-2,
    supports the diagnosis alongside nuclear STAT6.
  evidence:
  - reference: PMID:26722515
    reference_title: "Immunohistochemical detection of STAT6, CD34, CD99 and BCL-2 for diagnosing solitary fibrous tumors/hemangiopericytomas."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: 'CD34 was positive in 47 cases (47/53, sensitivity 88.7%)'
    explanation: Supports CD34 positivity as a characteristic SFT immunophenotype.
- name: Big-IGF-II
  biomarker_term:
    preferred_term: Insulin-Like Growth Factor II
    term:
      id: NCIT:C16744
      label: Insulin-Like Growth Factor II
  notes: >-
    Incompletely processed insulin-like growth factor II precursor secreted by a
    subset of SFTs; the biochemical mediator of Doege-Potter paraneoplastic
    hypoglycemia. Suppressed insulin and IGF-I with an elevated IGF-II:IGF-I ratio
    supports the diagnosis of non-islet-cell tumor hypoglycemia.
genetic:
- name: NAB2-STAT6 fusion
  gene_term:
    preferred_term: STAT6
    term:
      id: hgnc:11368
      label: STAT6
  variant_origin: SOMATIC
  notes: >-
    The recurrent NAB2-STAT6 fusion (NAB2 hgnc:7627; STAT6 hgnc:11368) is the
    pathognomonic somatic driver of SFT. It arises from an intrachromosomal
    rearrangement on 12q13; its protein product accumulates in the nucleus and is
    detectable by STAT6 immunohistochemistry.
  evidence:
  - reference: PMID:23313954
    reference_title: "Whole-exome sequencing identifies a recurrent NAB2-STAT6 fusion in solitary fibrous tumors."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Here, we describe the identification of a NAB2-STAT6 fusion from whole-exome
      sequencing of 17 SFTs.
    explanation: Identifies the somatic NAB2-STAT6 fusion as the genetic basis of SFT.
- name: NAB2 (NAB2-STAT6 fusion partner)
  gene_term:
    preferred_term: NAB2
    term:
      id: hgnc:7627
      label: NAB2
  variant_origin: SOMATIC
  notes: >-
    NAB2 is the 5' partner of the pathognomonic NAB2-STAT6 fusion. The
    intrachromosomal 12q13 rearrangement joins the truncated NAB2 transcriptional
    repressor domain to the STAT6 transactivation domain, converting NAB2 from an
    EGR1-target repressor into an aberrant activator. Captured as a separate gene
    entry for gene-based discoverability alongside STAT6 (hgnc:11368).
  evidence:
  - reference: PMID:23313954
    reference_title: "Whole-exome sequencing identifies a recurrent NAB2-STAT6 fusion in solitary fibrous tumors."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Here, we describe the identification of a NAB2-STAT6 fusion from whole-exome
      sequencing of 17 SFTs.
    explanation: Identifies NAB2 as the 5' partner gene of the somatic SFT-defining fusion.
treatments:
- name: Surgical Resection
  description: >-
    Complete surgical resection is the cornerstone of curative treatment for
    localized SFT; meningeal SFTs are managed by gross total or subtotal resection.
  treatment_term:
    preferred_term: surgical procedure
    term:
      id: MAXO:0000004
      label: surgical procedure
  therapeutic_modality: SURGERY
  evidence:
  - reference: PMID:42149317
    reference_title: "Systemic Therapy for Solitary Fibrous Tumor."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Complete surgical resection constitutes the cornerstone of treatment for
      localized disease
    explanation: Establishes surgery as the primary curative treatment for localized SFT.
- name: Postoperative Radiotherapy
  description: >-
    Adjuvant radiotherapy is used for meningeal/intracranial SFT after resection to
    reduce local recurrence, given the high recurrence risk of these tumors.
  treatment_term:
    preferred_term: radiation therapy
    term:
      id: MAXO:0000014
      label: radiation therapy
  therapeutic_modality: RADIOTHERAPY
  evidence:
  - reference: PMID:40354004
    reference_title: "Meningeal malignant solitary fibrous tumor with multiple recurrence, extracranial extension, cervical lymph node metastases: case report and review of the literature."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Postoperative radiotherapy (PORT) whether gross total resection (GTR) or
      subtotal resection (STR) may be the optimal treatment strategy
    explanation: >-
      Supports adjuvant radiotherapy after resection of meningeal malignant SFT.
- name: Antiangiogenic Therapy
  description: >-
    Antiangiogenic tyrosine kinase inhibitors (e.g., pazopanib) are the standard
    systemic backbone for locally advanced or metastatic non-dedifferentiated SFT.
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: pazopanib
      term:
        id: CHEBI:71219
        label: pazopanib
  therapeutic_modality: SMALL_MOLECULE
  target_mechanisms:
  - target: Fibroblastic Proliferation
    treatment_effect: INHIBITS
    description: >-
      Antiangiogenic tyrosine kinase inhibitors target the tumor angiogenesis
      (GO:0001525) that supports the proliferating fibroblastic compartment.
  evidence:
  - reference: PMID:42149317
    reference_title: "Systemic Therapy for Solitary Fibrous Tumor."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Antiangiogenic agents have shown promising outcomes, particularly in
      non-dedifferentiated SFT, and are increasingly favored by some as first-line
      options.
    explanation: >-
      Supports antiangiogenic therapy as the standard systemic backbone for advanced SFT.
- name: Somatostatin Analogue Therapy
  description: >-
    Somatostatin analogues (octreotide, lanreotide) can help control paraneoplastic
    hypoglycemia in Doege-Potter syndrome when complete resection is not feasible.
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: octreotide
      term:
        id: CHEBI:7726
        label: octreotide
  therapeutic_modality: PEPTIDE
  target_mechanisms:
  - target: Paraneoplastic Big-IGF-II Secretion (Doege-Potter Syndrome)
    treatment_effect: INHIBITS
    description: >-
      Somatostatin analogues suppress tumor secretion of Big-IGF-II, mitigating
      the paraneoplastic driver of Doege-Potter hypoglycemia.
  evidence:
  - reference: PMID:38441351
    reference_title: "Effective management of recurrent Doege-Potter syndrome with somatostatin-analogues: A case report."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The somatostatin-analogue Lanreotide was successfully used after tumor
      debulking surgery (R2-resection) to maintain adequate blood glucose control.
    explanation: >-
      Supports somatostatin analogues for controlling Doege-Potter hypoglycemia when
      resection is incomplete.
references:
- reference: PMID:22575866
  title: >-
    Solitary fibrous tumor: a clinicopathological study of 110 cases and proposed
    risk assessment model.

📚

References & Deep Research

References

1

PMID:22575866

Solitary fibrous tumor: a clinicopathological study of 110 cases and proposed risk assessment model.

No top-level findings curated for this source.

Deep Research

1

Falcon ▸

Visual Evidence: Demicco Risk Model Table

Edison Scientific Literature 43 citations 2026-06-08T16:43:50.553537

1. Disease Information

1.1 Concise overview

Solitary fibrous tumor (SFT) is a rare fibroblastic mesenchymal neoplasm that can arise in many anatomical sites and often behaves indolently but has an unpredictable propensity for local recurrence and distant metastasis (ren2024advancesinthe pages 1-2, janik2023diagnosticsandtreatment pages 1-2). A defining molecular hallmark is the NAB2::STAT6 gene fusion, and nuclear STAT6 immunohistochemistry (IHC) is widely used as a surrogate diagnostic marker (ren2024advancesinthe pages 1-2, ren2024advancesinthe pages 10-12, janik2023diagnosticsandtreatment pages 1-2).

Recent synthesis characterizes SFT as “a rare fibroblastic mesenchymal neoplasm” (Ren 2024, published Aug 2024) (https://doi.org/10.1007/s10555-024-10204-8) (ren2024advancesinthe pages 1-2).

1.2 Key identifiers (availability in retrieved sources)

MONDO: MONDO:0016238 (OpenTargets) (OpenTargets Search: Solitary fibrous tumor)
Other identifiers (ICD-10/ICD-11, MeSH, Orphanet, OMIM): Not extracted from the retrieved full-text evidence in this run; should be completed by direct lookup in ICD/MeSH/Orphanet/OMIM.

1.3 Synonyms / alternative names

Hemangiopericytoma (HPC): legacy terminology; many CNS and soft tissue tumors formerly classified as HPC are now encompassed within SFT under WHO reclassifications (wu2024clinicaloutcomesof pages 1-2, piccinelli2024demographicandclinical pages 1-2).

1.4 Evidence sources (individual patient vs aggregated)

This report integrates: - Aggregated cohort/registry evidence (SEER analysis; CNS cohort studies; systematic reviews) (wu2024clinicaloutcomesof pages 1-2, piccinelli2024demographicandclinical pages 1-2, tolstrup2024riskfactorsfor pages 1-2). - Aggregated review evidence (molecular/clinical reviews) (ren2024advancesinthe pages 1-2, janik2023diagnosticsandtreatment pages 1-2). - Individual case-based molecular pathology (e.g., intraosseous/epithelioid variants) used mainly for diagnostic marker panels and molecular confirmation methods (argyris2024primaryintraosseoussolitary pages 1-2, zhao2024epithelioidsolitaryfibrous pages 1-2).

2. Etiology

2.1 Disease causal factors (molecular/genetic mechanism)

SFT is primarily driven by a somatic intrachromosomal rearrangement on chromosome 12q13 producing the NAB2–STAT6 fusion (ren2024advancesinthe pages 1-2, zhao2024epithelioidsolitaryfibrous pages 1-2). Mechanistically, the fusion alters transcriptional control: Ren 2024 states the fusion “transforms NAB2 into a transcriptional activator, activating early growth response 1 (EGR1)” (https://doi.org/10.1007/s10555-024-10204-8; Aug 2024) (ren2024advancesinthe pages 1-2).

2.2 Risk factors

Evidence in the retrieved corpus supports prognostic risk factors (risk of recurrence/metastasis) more than pre-disease exposures: - The 2024 systematic review found the most consistent recurrence predictors were high mitotic index, high Ki‑67, and necrosis (Tolstrup 2024; Jan 2024) (https://doi.org/10.3389/fsurg.2024.1332421) (tolstrup2024riskfactorsfor pages 1-2). - Molecular risk factors/biomarkers suggested to refine risk include TERT promoter mutations and TP53 alterations, with additional factors (APAF1 inactivation, etc.) variably reported (yao2024prognosticanalysisof pages 1-2, janik2023diagnosticsandtreatment pages 16-17, tolstrup2024riskfactorsfor pages 1-2).

Pre-disease environmental/lifestyle risks: not established in the retrieved sources; SFT is generally treated as a sporadic tumor entity.

2.3 Protective factors

No protective genetic/environmental factors were identified in the retrieved evidence.

2.4 Gene–environment interaction

No gene–environment interaction evidence was identified in the retrieved evidence.

3. Phenotypes

3.1 Clinical presentation (common patterns)

SFTs often present as slow-growing masses and can be asymptomatic depending on site (ren2024advancesinthe pages 1-2, janik2023diagnosticsandtreatment pages 1-2). Symptomatology is largely site-driven (compression, pain, neurologic deficits in CNS, etc.). In malignant pleural SFT, a majority in one cohort were symptomatic (62%) (ricciardi2023malignantsolitaryfibrous pages 1-2).

3.2 Histopathologic phenotype

Core morphologic phenotype includes spindle-to-ovoid cells with a prominent branching (“staghorn”) vasculature. For example, an intraosseous case review described “a haphazardly-arranged population of spindled-to-ovoid cells surrounding a prominent, branching and hyalinized vasculature” (Argyris 2024; Dec 2024) (https://doi.org/10.1007/s12105-024-01735-1) (argyris2024primaryintraosseoussolitary pages 1-2).

3.3 Suggested HPO terms (examples; frequency generally not quantified in retrieved evidence)

Because SFT manifestations are site-dependent, suggested HPO terms are necessarily generic: - Mass / tumor: HP:0002664 (Neoplasm) (suggested) - Localized pain: HP:0012531 (Pain) (suggested) - Compression symptoms (site-specific): e.g., HP:0002664 (Neoplasm) + organ-specific dysfunction terms (suggested)

Note: The retrieved evidence did not provide robust phenotype frequency tables beyond site distributions in malignant cohorts (piccinelli2024demographicandclinical pages 1-2).

4. Genetic / Molecular Information

4.1 Causal gene(s) and hallmark alteration

NAB2::STAT6 gene fusion (driver/defining event) (ren2024advancesinthe pages 1-2, argyris2024primaryintraosseoussolitary pages 1-2, zhao2024epithelioidsolitaryfibrous pages 1-2).
Common fusion variants reported as frequent include NAB2ex4–STAT6ex2 and NAB2ex6–STAT6ex16/ex17 (Ren 2024; Aug 2024) (ren2024advancesinthe pages 1-2).

4.2 Somatic vs germline

SFT is generally treated as nonhereditary/sporadic. An RNA-therapy SFT model paper explicitly states: “This nonhereditary cancer is the result of an environmental intrachromosomal gene fusion between NAB2 and STAT6 on chromosome 12” (Li 2023; Jun 2023) (https://doi.org/10.3390/cancers15123127) ().

4.3 Diagnostic molecular surrogates

STAT6 IHC is widely used as a surrogate for NAB2–STAT6 fusion. A key quantitative statement from Ren 2024 notes: “diffuse and robust nuclear expression of STAT6 through IHC was documented in 100% of cases, with concurrent gene fusion detection in 92% of cases through RT-PCR” (https://doi.org/10.1007/s10555-024-10204-8; Aug 2024) (ren2024advancesinthe pages 10-12).

4.4 Additional molecular alterations (progression/aggressiveness)

In an extrameningeal cohort (n=111), TP53 and TERT promoter mutations were associated with progression in several patients (Yao 2024; Jan 2024) (https://doi.org/10.3389/fonc.2023.1272090) (yao2024prognosticanalysisof pages 1-2).
The WHO-referenced clinical review highlights aggressive-associated findings such as TERT promoter mutations and TP53 immunopositivity with loss of APAF1 (janik2023diagnosticsandtreatment pages 16-17).

4.5 Epigenetic information

Not extracted from retrieved evidence in this run.

4.6 Suggested GO / CL terms (mechanism-linked; examples)

GO:0006355 (Regulation of transcription, DNA-templated) — consistent with fusion-driven transcriptional reprogramming (suggested; supported mechanistically by EGR1 activation narrative) (ren2024advancesinthe pages 1-2).
CL:0002554 (fibroblast) — consistent with fibroblastic/mesenchymal tumor lineage (suggested) (ren2024advancesinthe pages 1-2, janik2023diagnosticsandtreatment pages 1-2).

5. Environmental Information

No specific toxins, radiation, lifestyle exposures, or infectious agents were identified as causal or modifying factors in the retrieved evidence.

6. Mechanism / Pathophysiology

6.1 Causal chain (current understanding)

Initiating lesion: intrachromosomal rearrangement on chromosome 12q13 → NAB2::STAT6 fusion (ren2024advancesinthe pages 1-2, zhao2024epithelioidsolitaryfibrous pages 1-2).
Transcriptional reprogramming: fusion alters NAB2/STAT6 function; review states it “transforms NAB2 into a transcriptional activator” and activates EGR1 programs (ren2024advancesinthe pages 1-2).
Cellular consequences: altered enhancer/promoter activity and gene-expression programs consistent with proliferative and pro-survival states; mechanistic model systems show the fusion can be studied via inducible expression systems and primary tumor chromatin profiling (hill2025nab2stat6drivesan pages 4-6, hill2025nab2stat6drivesan pages 1-3).
Clinical manifestation: tumor formation with characteristic fibroblastic morphology and hypervascular “staghorn” vasculature; malignant transformation/progression correlates with proliferation/necrosis and additional molecular lesions (TP53/TERT/APAF1) (argyris2024primaryintraosseoussolitary pages 1-2, janik2023diagnosticsandtreatment pages 16-17, yao2024prognosticanalysisof pages 1-2).

6.2 Upstream vs downstream

Upstream (driver/defining): NAB2::STAT6 fusion (ren2024advancesinthe pages 1-2, argyris2024primaryintraosseoussolitary pages 1-2).
Downstream (progression modifiers): mitotic index, Ki-67, necrosis and secondary alterations (TERT promoter mutation, TP53 alteration, APAF1 loss) that correlate with recurrence/progression (tolstrup2024riskfactorsfor pages 1-2, yao2024prognosticanalysisof pages 1-2, janik2023diagnosticsandtreatment pages 16-17).

7. Anatomical Structures Affected

7.1 Organ-level distribution (malignant SFT registry evidence)

A large SEER analysis of 1,134 malignant SFT cases (2000–2019) reported primary sites: chest 28–29%, CNS 22–23%, head and neck 11%, pelvis 11%, extremities 10%, abdomen 10%, retroperitoneum 6% (Piccinelli 2024; Sep 2024) (https://doi.org/10.3390/cancers16193331) (piccinelli2024demographicandclinical pages 1-2, piccinelli2024demographicandclinical pages 2-4).

7.2 Suggested UBERON terms (examples)

UBERON:0002048 (lung) / pleura-adjacent thoracic tissues (thoracic SFT common) (suggested; supported by pleural predominance in reviews and SEER distribution) (ren2024advancesinthe pages 1-2, piccinelli2024demographicandclinical pages 1-2)
UBERON:0000955 (brain) / meninges (CNS SFT) (suggested; CNS cohorts) (wu2024clinicaloutcomesof pages 1-2)
UBERON:0002385 (trunk) and region/site-specific structures depending on presentation (suggested)

8. Temporal Development

8.1 Onset

Typical diagnosis is in middle age to older adults; an extrameningeal review notes presentation often in the 50s–70s (janik2023diagnosticsandtreatment pages 1-2). SEER malignant cohort median age was 60 years (piccinelli2024demographicandclinical pages 2-4).

8.2 Progression and disease course

SFT may recur late; a systematic review reports recurrence estimates around 10–20% in many studies, with longer follow-up cohorts reporting >30% (Tolstrup 2024; Jan 2024) (tolstrup2024riskfactorsfor pages 2-3). CNS SFT demonstrates grade-dependent outcomes with median PFS/OS decreasing from grade 1 to grade 3 (wu2024clinicaloutcomesof pages 1-2).

9. Inheritance and Population

9.1 Epidemiology

Rarity/incidence: one recent review reports 1–2 per million (Ren 2024; Aug 2024) (ren2024advancesinthe pages 1-2); another review reports ~0.061 per 100,000/year and SFTs representing <2% of soft tissue tumors/masses (Janik 2023; Dec 2023) (janik2023diagnosticsandtreatment pages 1-2).

9.2 Population demographics

SEER malignant cohort: 49% male; 87% underwent surgery; stage distribution localized 42%, locally advanced 35%, metastatic 13% (piccinelli2024demographicandclinical pages 1-2).

9.3 Inheritance

No Mendelian inheritance pattern is supported; evidence emphasizes nonhereditary/sporadic nature ().

10. Diagnostics

10.1 Pathology and immunohistochemistry (IHC)

Core IHC markers: STAT6 (nuclear) and CD34 (cytoplasmic) are emphasized as mainstays in extrameningeal SFT diagnosis (Janik 2023; Dec 2023) (janik2023diagnosticsandtreatment pages 1-2).
STAT6 as fusion surrogate: “STAT6 IHC nuclear staining … has been validated as a valuable surrogate marker for detecting NAB2-STAT6 gene fusion” (Ren 2024; Aug 2024) (ren2024advancesinthe pages 10-12), with the quantitative concordance statement noted above (100% STAT6 nuclear IHC; 92% RT-PCR fusion detection) (ren2024advancesinthe pages 10-12).
Diagnostic caveat: specificity is imperfect because STAT6 expression can occur in other sarcomas (Ren 2024) (ren2024advancesinthe pages 10-12).

10.2 Molecular confirmation options

Molecular confirmation and characterization may use RT-PCR, targeted RNA sequencing/NGS fusion panels, WGS/WES/RNA-seq, or FISH depending on specimen and clinical need (ren2024advancesinthe pages 10-12, argyris2024primaryintraosseoussolitary pages 1-2). A concrete implementation example is an intraosseous SFT case that used an RNA-based NGS fusion panel (Arriba software) plus a DNA NGS panel and FISH for other differential considerations (Argyris 2024; Dec 2024) (argyris2024primaryintraosseoussolitary pages 1-2).

10.3 Differential diagnosis (marker panels)

An epithelioid SFT series noted STAT6/CD34 positivity with negative keratins and other lineage markers, supporting broad differential exclusion in unusual morphologies (Zhao 2024; Oct 2024) (https://doi.org/10.1186/s13000-024-01564-4) (zhao2024epithelioidsolitaryfibrous pages 1-2).

10.4 Imaging

Imaging is important for localization/staging but not diagnostic alone; histologic confirmation is required (review-level statement) (ren2024advancesinthe pages 1-2).

11. Outcome / Prognosis

11.1 Prognostic models and key statistics

A compact quantitative summary of major outcome and prognostic evidence is provided in the table below.

Item	Key numbers/findings	Population/context	Source (URL; year)	Evidence citation id
Incidence / rarity	Incidence reported at ~0.061 per 100,000/year; also described as 1–2 per million people/year; SFTs account for <2% of soft tissue tumors/masses	General / extrameningeal SFT in reviews	Janik et al., Cancers (https://doi.org/10.3390/cancers15245854; 2023); Ren et al., Cancer Metastasis Rev. (https://doi.org/10.1007/s10555-024-10204-8; 2024)	(janik2023diagnosticsandtreatment pages 1-2, ren2024advancesinthe pages 1-2)
Recurrence / metastasis rates	Reviews cite 10–30% recurrence after resection; recurrence/metastasis rate broadly 10–40%; longer-follow-up cohorts may report recurrence >30%	Mixed non-CNS SFT cohorts, especially resected torso/extremity disease	Tolstrup et al., Front Surg (https://doi.org/10.3389/fsurg.2024.1332421; 2024); Zhang et al., Nat Commun (https://doi.org/10.1038/s41467-023-43249-4; 2023)	(tolstrup2024riskfactorsfor pages 1-2, tolstrup2024riskfactorsfor pages 2-3, yao2024prognosticanalysisof pages 1-2)
SEER malignant SFT cohort	n=1,134 malignant SFTs; sites: chest 28–29%, CNS 22–23%, head/neck 11%, pelvis 11%, extremities 10%, abdomen 10%, retroperitoneum 6%; stage: localized 42%, locally advanced 35%, metastatic 13%; surgery in 87%	SEER 2000–2019 malignant SFT population-based cohort	Piccinelli et al., Cancers (https://doi.org/10.3390/cancers16193331; 2024)	(piccinelli2024demographicandclinical pages 1-2, piccinelli2024demographicandclinical pages 2-4)
SEER prognostic factors	Higher cancer-specific mortality with locally advanced stage HR 1.6, metastatic stage HR 2.9, non-surgical management HR 3.6, tumor size 9–15.9 cm HR 1.6, ≥16 cm HR 1.9	Multivariable competing-risks analysis in SEER malignant SFT cohort	Piccinelli et al., Cancers (https://doi.org/10.3390/cancers16193331; 2024)	(piccinelli2024demographicandclinical pages 1-2)
CNS WHO grade outcomes	Grade 1: median PFS 105 mo, OS 199 mo; Grade 2: PFS 77 mo, OS 145 mo; Grade 3: PFS 44 mo, OS 112 mo; cohort counts: grade 1 86, grade 2 35, grade 3 25	Reclassified CNS SFT/HPC cohort, n=146, per WHO 2021 CNS classification	Wu et al., J Neurosurg (https://doi.org/10.3171/2023.4.JNS23147; 2024)	(wu2024clinicaloutcomesof pages 1-2)
CNS recurrence / mortality / treatment effect	Local recurrence in 61/146; deaths 31/146, of which 27/31 (87.1%) disease-related; subtotal resection worsened PFS (HR 4.648) and OS (HR 3.217); grade 3 worsened PFS (HR 5.814) and OS (HR 3.433)	Same CNS cohort	Wu et al., J Neurosurg (https://doi.org/10.3171/2023.4.JNS23147; 2024)	(wu2024clinicaloutcomesof pages 1-2)
Pleural malignant SFT outcomes	5-year OS 81.2%, 5-year DFS 77.4%; recurrence in 9/34 (26.5%); median follow-up 111 months; median age 67 years	Single-center cohort of malignant pleural SFT, n=34	Ricciardi et al., J Clin Med (https://doi.org/10.3390/jcm12030966; 2023)	(ricciardi2023malignantsolitaryfibrous pages 1-2)
Pleural malignant SFT prognostic factors	Worse OS: necrosis, nuclear atypia, tumor size >11.5 cm, relapse/progression; worse DFS: non-radical resection, larger size, necrosis, nuclear atypia, pleural pattern; Tapias score best predicted OS/DFS	Same malignant pleural SFT cohort	Ricciardi et al., J Clin Med (https://doi.org/10.3390/jcm12030966; 2023)	(ricciardi2023malignantsolitaryfibrous pages 1-2)
Recurrence risk factors across studies	Most consistent adverse factors: high mitotic index, necrosis, high Ki-67 index; additional variably associated factors: age, tumor size, sex, margins, location, pleomorphism, hypercellularity, dedifferentiation, CD34, TP53, APAF1, TERT promoter mutation, NAB2::STAT6 variant	81 retrospective studies in systematic review of resected torso/extremity SFT	Tolstrup et al., Front Surg (https://doi.org/10.3389/fsurg.2024.1332421; 2024)	(tolstrup2024riskfactorsfor pages 2-3, tolstrup2024riskfactorsfor pages 1-2)
Modified Demicco model performance caveat	In 111 extrameningeal SFTs, progression still occurred in 3/74 low-risk and 7/21 intermediate-risk cases; TP53 alterations: progression in 3/5; TERT promoter mutations: progression in 3/4 followed cases	East China extrameningeal SFT series, n=111	Yao et al., Front Oncol (https://doi.org/10.3389/fonc.2023.1272090; 2024)	(yao2024prognosticanalysisof pages 1-2)
Demicco risk model variables	WHO-recommended Demicco models use age, tumor size, mitotic count, and in the modified 4-variable model necrosis to assign low/intermediate/high metastatic risk	Risk stratification for extrameningeal SFT	Janik et al., Cancers (https://doi.org/10.3390/cancers15245854; 2023); image extract of Demicco table	(janik2023diagnosticsandtreatment pages 16-17, janik2023diagnosticsandtreatment media 2935871a)
WHO/CNS grading variables	CNS WHO grading uses mitotic activity and necrosis: grade 1 <2.5 mitoses/mm², grade 2 ≥2.5 mitoses/mm², grade 3 ≥2.5 mitoses/mm² plus necrosis	WHO 2021 CNS SFT framework	Wu et al., J Neurosurg (https://doi.org/10.3171/2023.4.JNS23147; 2024)	(wu2024clinicaloutcomesof pages 1-2)

Table: This table compiles the main quantitative epidemiology, prognosis, and risk-model findings for solitary fibrous tumor from the gathered evidence. It is useful as a compact reference for incidence, recurrence, survival, and the variables used in current risk stratification systems.

11.2 Risk stratification (Demicco and others)

WHO-referenced models use age, tumor size, mitotic count, and (in a 4-variable modification) necrosis to stratify metastatic risk (janik2023diagnosticsandtreatment pages 16-17). The extracted table image below shows the Demicco scoring framework as presented in a 2023 review (janik2023diagnosticsandtreatment media 2935871a).

11.3 Evidence-based prognostic factors

The 2024 systematic review identified mitotic index, necrosis, and Ki‑67 as the most solid predictors of recurrence after resection across multiple retrospective studies (tolstrup2024riskfactorsfor pages 1-2). Large-registry evidence indicates stage, surgery, and tumor size independently predict cancer-specific mortality in malignant SFT (piccinelli2024demographicandclinical pages 1-2).

12. Treatment

12.1 Localized disease

Surgery: Radical/en bloc resection with negative margins is the cornerstone of treatment (review consensus) (ren2024advancesinthe pages 10-12, janik2023diagnosticsandtreatment pages 1-2).
Radiotherapy: In CNS SFT, gross-total resection prolongs PFS/OS; adjuvant radiotherapy appears beneficial after subtotal resection (Wu 2024; Jan 2024) (https://doi.org/10.3171/2023.4.JNS23147) (wu2024clinicaloutcomesof pages 1-2).

12.2 Advanced/metastatic disease (systemic therapy)

Evidence synthesized in recent reviews indicates: - Conventional chemotherapy has limited durable benefit; one review states conventional chemotherapy is “not associated with long-term positive effects” (Janik 2023; Dec 2023) (janik2023diagnosticsandtreatment pages 13-14). - Anti-angiogenic therapy (TKIs/VEGF-pathway inhibition) shows more consistent disease control and higher response rates by Choi criteria. Janik 2023 summarizes pazopanib as “the best first-line treatment” in the advanced setting with reported Choi partial responses and high disease-control rates, and reports activity for axitinib and sunitinib with median PFS on the order of months (janik2023diagnosticsandtreatment pages 13-14). - A broader systemic-therapy synthesis reports typical outcomes such as pazopanib median PFS ~5–6 months in aggressive SFT trials (with higher Choi response rates than RECIST) and sunitinib median PFS ~6–7 months in series; temozolomide+bevacizumab has reported median PFS ~9.7–10.8 months in retrospective analyses (martinbroto2021acomprehensivereview pages 15-16).

12.3 Clinical trials (real-world implementation)

ClinicalTrials.gov evidence in this run identified completed phase II studies specifically in SFT: - Axitinib in advanced SFT (NCT02261207; Phase II; completed; n=17) (). - Pazopanib in SFT (NCT02066285; Phase II; completed; n=96) ().

Note: The retrieved trial records provide trial existence/phase/enrollment; numerical efficacy endpoints were not extracted from the trial registry chunks in this run.

12.4 Suggested MAXO terms (examples)

MAXO:0000601 (Surgical resection) (suggested; supported by standard-of-care) (janik2023diagnosticsandtreatment pages 1-2)
MAXO:0000016 (Radiotherapy) (suggested; CNS adjuvant RT evidence) (wu2024clinicaloutcomesof pages 1-2)
MAXO:0000750 (Targeted therapy) / antiangiogenic TKI therapy (suggested; multiple TKI evidence) (janik2023diagnosticsandtreatment pages 13-14)

13. Prevention

No established primary prevention strategies are supported in the retrieved evidence. Secondary prevention largely corresponds to surveillance/follow-up to detect late recurrence (review consensus) (janik2023diagnosticsandtreatment pages 1-2, tolstrup2024riskfactorsfor pages 1-2).

14. Other Species / Natural Disease

Robust evidence for naturally occurring SFT in non-human species was not identified in the retrieved, SFT-focused corpus for this run. (A separate veterinary sarcoma imaging/metastasis paper retrieved was not SFT-specific and is therefore not used to support SFT natural-history claims.)

15. Model Organisms / Experimental Models

Recent and emerging SFT research leverages engineered and patient-derived models: - CRISPR/SpCas9 engineered in vitro models harboring NAB2–STAT6, used to evaluate fusion-specific antisense oligonucleotides and CRISPR/CasRx approaches (Li 2023; Jun 2023) (https://doi.org/10.3390/cancers15123127) (). - Inducible fusion-expression cell models for chromatin/transcriptional studies and use of primary human tumor material for ChIP-seq-based mapping of fusion-associated binding (hill2025nab2stat6drivesan pages 4-6). - Patient-derived xenograft (mouse) models are reported in RNA/antisense oligonucleotide development literature (e.g., STAT6-targeting ASO studies) (Li 2024; Jun 2024) (https://doi.org/10.1016/j.omtn.2024.102154) ().

Visual Evidence: Demicco Risk Model Table

The following image extract shows a WHO-referenced Demicco risk stratification table (variables: age, tumor size, mitotic count, necrosis) as presented in a 2023 review. (janik2023diagnosticsandtreatment media 2935871a)

Notes on Evidence Gaps

ICD/MeSH/Orphanet/OMIM identifiers, detailed phenotype frequencies, and epigenomic profiling summaries were not present in the retrieved evidence snippets and should be filled via targeted database queries.
Some systemic therapy efficacy statistics cited here derive from review-level syntheses; for knowledge-base ingestion, confirm each numerical endpoint against the original trial/series publications referenced in those reviews.

References

(OpenTargets Search: Solitary fibrous tumor): Open Targets Query (Solitary fibrous tumor, 15 results). Buniello, A. et al. (2025). Open Targets Platform: facilitating therapeutic hypotheses building in drug discovery. Nucleic Acids Research.
(ren2024advancesinthe pages 1-2): Chongmin Ren, Gina Z D'Amato, Francis J Hornicek, Hao Tao, and Zhenfeng Duan. Advances in the molecular biology of the solitary fibrous tumor and potential impact on clinical applications. Cancer Metastasis Reviews, 43:1337-1352, Aug 2024. URL: https://doi.org/10.1007/s10555-024-10204-8, doi:10.1007/s10555-024-10204-8. This article has 21 citations.
(piccinelli2024demographicandclinical pages 1-2): Mattia Luca Piccinelli, Kyle Law, Reha-Baris Incesu, Stefano Tappero, Cristina Cano Garcia, Francesco Barletta, Simone Morra, Lukas Scheipner, Andrea Baudo, Zhe Tian, Stefano Luzzago, Francesco Alessandro Mistretta, Matteo Ferro, Fred Saad, Shahrokh F. Shariat, Luca Carmignani, Sascha Ahyai, Nicola Longo, Alberto Briganti, Felix K. H. Chun, Carlo Terrone, Derya Tilki, Ottavio de Cobelli, Gennaro Musi, and Pierre I. Karakiewicz. Demographic and clinical characteristics of malignant solitary fibrous tumors: a seer database analysis. Cancers, 16:3331, Sep 2024. URL: https://doi.org/10.3390/cancers16193331, doi:10.3390/cancers16193331. This article has 12 citations.
(janik2023diagnosticsandtreatment pages 1-2): Anna Maria Janik, Anna Terlecka, Mateusz J. Spałek, Kjetil Boye, Bartłomiej Szostakowski, Paulina Chmiel, Anna Szumera-Ciećkiewicz, Klaudia Bobak, Tomasz Świtaj, Piotr Rutkowski, and Anna M. Czarnecka. Diagnostics and treatment of extrameningeal solitary fibrous tumors. Cancers, 15:5854, Dec 2023. URL: https://doi.org/10.3390/cancers15245854, doi:10.3390/cancers15245854. This article has 21 citations.
(ren2024advancesinthe pages 10-12): Chongmin Ren, Gina Z D'Amato, Francis J Hornicek, Hao Tao, and Zhenfeng Duan. Advances in the molecular biology of the solitary fibrous tumor and potential impact on clinical applications. Cancer Metastasis Reviews, 43:1337-1352, Aug 2024. URL: https://doi.org/10.1007/s10555-024-10204-8, doi:10.1007/s10555-024-10204-8. This article has 21 citations.
(wu2024clinicaloutcomesof pages 1-2): Yingxi Wu, Tianzhi Zhao, Yaning Cai, Min Zheng, Yunze Zhang, Yan Qu, and Qing Cai. Clinical outcomes of solitary fibrous tumors and hemangiopericytomas and risk factors related to recurrence and survival based on the 2021 who classification of central nervous system tumors. Journal of Neurosurgery, 140(1):69-79, Jan 2024. URL: https://doi.org/10.3171/2023.4.jns23147, doi:10.3171/2023.4.jns23147. This article has 27 citations and is from a domain leading peer-reviewed journal.
(tolstrup2024riskfactorsfor pages 1-2): Johan Tolstrup, Anand Loya, Ninna Aggerholm-Pedersen, Louise Preisler, and Luit Penninga. Risk factors for recurrent disease after resection of solitary fibrous tumor: a systematic review. Frontiers in Surgery, Jan 2024. URL: https://doi.org/10.3389/fsurg.2024.1332421, doi:10.3389/fsurg.2024.1332421. This article has 21 citations.
(argyris2024primaryintraosseoussolitary pages 1-2): Prokopios P. Argyris, Kristie L. Wise, Kristin K. McNamara, Daniel M. Jones, and John R. Kalmar. Primary intraosseous solitary fibrous tumor of the mandible: report of a diagnostically challenging case with nab2::stat6 fusion and review of the literature. Head and neck pathology, 18 1:128, Dec 2024. URL: https://doi.org/10.1007/s12105-024-01735-1, doi:10.1007/s12105-024-01735-1. This article has 1 citations and is from a peer-reviewed journal.
(zhao2024epithelioidsolitaryfibrous pages 1-2): Lina Zhao, Jiajing Ma, Jiacai Ren, Jingping Yuan, Huihua He, Yabing Huang, and Honglin Yan. Epithelioid solitary fibrous tumors from cns and soft tissues: an unusual morphologic variant. Diagnostic Pathology, Oct 2024. URL: https://doi.org/10.1186/s13000-024-01564-4, doi:10.1186/s13000-024-01564-4. This article has 2 citations and is from a peer-reviewed journal.
(yao2024prognosticanalysisof pages 1-2): Chen-chen Yao, Jian Zhou, Xiao Li, Jun Yang, Gang Chen, Jia Wei, Qin-he Fan, and Qi-xing Gong. Prognostic analysis of extrameningeal solitary fibrous tumor using the modified demicco model: a clinicopathologic study of 111 chinese cases. Frontiers in Oncology, Jan 2024. URL: https://doi.org/10.3389/fonc.2023.1272090, doi:10.3389/fonc.2023.1272090. This article has 2 citations.
(janik2023diagnosticsandtreatment pages 16-17): Anna Maria Janik, Anna Terlecka, Mateusz J. Spałek, Kjetil Boye, Bartłomiej Szostakowski, Paulina Chmiel, Anna Szumera-Ciećkiewicz, Klaudia Bobak, Tomasz Świtaj, Piotr Rutkowski, and Anna M. Czarnecka. Diagnostics and treatment of extrameningeal solitary fibrous tumors. Cancers, 15:5854, Dec 2023. URL: https://doi.org/10.3390/cancers15245854, doi:10.3390/cancers15245854. This article has 21 citations.
(ricciardi2023malignantsolitaryfibrous pages 1-2): Sara Ricciardi, Delia Giovanniello, Luigi Carbone, Francesco Carleo, Marco Di Martino, Massimo Osvaldo Jaus, Sara Mantovani, Stefano Treggiari, Andrea Tornese, and Giuseppe Cardillo. Malignant solitary fibrous tumours of the pleura are not all the same: analysis of long-term outcomes and evaluation of risk stratification models in a large single-centre series. Journal of Clinical Medicine, 12:966, Jan 2023. URL: https://doi.org/10.3390/jcm12030966, doi:10.3390/jcm12030966. This article has 4 citations.
(hill2025nab2stat6drivesan pages 4-6): Connor M Hill, Alexandra Indeglia, Francis Picone, Maureen E Murphy, Cara Cipriano, Robert G Maki, and Alessandro Gardini. Nab2-stat6 drives an egr1-dependent neuroendocrine program in solitary fibrous tumors. Feb 2025. URL: https://doi.org/10.7554/elife.98072, doi:10.7554/elife.98072. This article has 7 citations.
(hill2025nab2stat6drivesan pages 1-3): Connor M Hill, Alexandra Indeglia, Francis Picone, Maureen E Murphy, Cara Cipriano, Robert G Maki, and Alessandro Gardini. Nab2-stat6 drives an egr1-dependent neuroendocrine program in solitary fibrous tumors. Feb 2025. URL: https://doi.org/10.7554/elife.98072, doi:10.7554/elife.98072. This article has 7 citations.
(piccinelli2024demographicandclinical pages 2-4): Mattia Luca Piccinelli, Kyle Law, Reha-Baris Incesu, Stefano Tappero, Cristina Cano Garcia, Francesco Barletta, Simone Morra, Lukas Scheipner, Andrea Baudo, Zhe Tian, Stefano Luzzago, Francesco Alessandro Mistretta, Matteo Ferro, Fred Saad, Shahrokh F. Shariat, Luca Carmignani, Sascha Ahyai, Nicola Longo, Alberto Briganti, Felix K. H. Chun, Carlo Terrone, Derya Tilki, Ottavio de Cobelli, Gennaro Musi, and Pierre I. Karakiewicz. Demographic and clinical characteristics of malignant solitary fibrous tumors: a seer database analysis. Cancers, 16:3331, Sep 2024. URL: https://doi.org/10.3390/cancers16193331, doi:10.3390/cancers16193331. This article has 12 citations.
(tolstrup2024riskfactorsfor pages 2-3): Johan Tolstrup, Anand Loya, Ninna Aggerholm-Pedersen, Louise Preisler, and Luit Penninga. Risk factors for recurrent disease after resection of solitary fibrous tumor: a systematic review. Frontiers in Surgery, Jan 2024. URL: https://doi.org/10.3389/fsurg.2024.1332421, doi:10.3389/fsurg.2024.1332421. This article has 21 citations.
(janik2023diagnosticsandtreatment media 2935871a): Anna Maria Janik, Anna Terlecka, Mateusz J. Spałek, Kjetil Boye, Bartłomiej Szostakowski, Paulina Chmiel, Anna Szumera-Ciećkiewicz, Klaudia Bobak, Tomasz Świtaj, Piotr Rutkowski, and Anna M. Czarnecka. Diagnostics and treatment of extrameningeal solitary fibrous tumors. Cancers, 15:5854, Dec 2023. URL: https://doi.org/10.3390/cancers15245854, doi:10.3390/cancers15245854. This article has 21 citations.
(janik2023diagnosticsandtreatment pages 13-14): Anna Maria Janik, Anna Terlecka, Mateusz J. Spałek, Kjetil Boye, Bartłomiej Szostakowski, Paulina Chmiel, Anna Szumera-Ciećkiewicz, Klaudia Bobak, Tomasz Świtaj, Piotr Rutkowski, and Anna M. Czarnecka. Diagnostics and treatment of extrameningeal solitary fibrous tumors. Cancers, 15:5854, Dec 2023. URL: https://doi.org/10.3390/cancers15245854, doi:10.3390/cancers15245854. This article has 21 citations.
(martinbroto2021acomprehensivereview pages 15-16): Javier Martin-Broto, Jose L. Mondaza-Hernandez, David S. Moura, and Nadia Hindi. A comprehensive review on solitary fibrous tumor: new insights for new horizons. Jun 2021. URL: https://doi.org/10.3390/cancers13122913, doi:10.3390/cancers13122913. This article has 87 citations.

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Subtypes

Pathophysiology

Histopathology

Pathograph

Phenotypes

Genetic Associations

Medical Actions

Biochemical Markers

Source YAML

References & Deep Research

References

Deep Research

1. Disease Information

1.1 Concise overview

1.2 Key identifiers (availability in retrieved sources)

1.3 Synonyms / alternative names

1.4 Evidence sources (individual patient vs aggregated)

2. Etiology

2.1 Disease causal factors (molecular/genetic mechanism)

2.2 Risk factors

2.3 Protective factors

2.4 Gene–environment interaction

3. Phenotypes

3.1 Clinical presentation (common patterns)

3.2 Histopathologic phenotype

3.3 Suggested HPO terms (examples; frequency generally not quantified in retrieved evidence)

4. Genetic / Molecular Information

4.1 Causal gene(s) and hallmark alteration

4.2 Somatic vs germline

4.3 Diagnostic molecular surrogates

4.4 Additional molecular alterations (progression/aggressiveness)

4.5 Epigenetic information

4.6 Suggested GO / CL terms (mechanism-linked; examples)

5. Environmental Information

6. Mechanism / Pathophysiology

6.1 Causal chain (current understanding)

6.2 Upstream vs downstream

7. Anatomical Structures Affected

7.1 Organ-level distribution (malignant SFT registry evidence)

7.2 Suggested UBERON terms (examples)

8. Temporal Development

8.1 Onset

8.2 Progression and disease course

9. Inheritance and Population

9.1 Epidemiology

9.2 Population demographics

9.3 Inheritance

10. Diagnostics

10.1 Pathology and immunohistochemistry (IHC)

10.2 Molecular confirmation options

10.3 Differential diagnosis (marker panels)

10.4 Imaging

11. Outcome / Prognosis

11.1 Prognostic models and key statistics

11.2 Risk stratification (Demicco and others)

11.3 Evidence-based prognostic factors

12. Treatment

12.1 Localized disease

12.2 Advanced/metastatic disease (systemic therapy)

12.3 Clinical trials (real-world implementation)

12.4 Suggested MAXO terms (examples)

13. Prevention

14. Other Species / Natural Disease

15. Model Organisms / Experimental Models

Visual Evidence: Demicco Risk Model Table

Notes on Evidence Gaps

Artifacts