Waldenstrom macroglobulinemia is an indolent B-cell neoplasm defined by bone marrow infiltration with lymphoplasmacytic lymphoma and secretion of a monoclonal IgM paraprotein. The disease is driven in most cases by MYD88 L265P and further shaped in a substantial subset by subclonal CXCR4 WHIM-like mutations. Morbidity reflects both marrow infiltration by the lymphoplasmacytic clone and the downstream effects of the IgM paraprotein, including hyperviscosity and peripheral neuropathy. Current disease-level management centers on observation for asymptomatic disease, fixed-duration chemoimmunotherapy, covalent BTK inhibition, and plasmapheresis for urgent paraprotein reduction.
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name: Waldenstrom Macroglobulinemia
creation_date: '2026-04-13T05:35:14Z'
updated_date: '2026-04-22T20:13:21Z'
category: Cancer
categories:
- Hematologic Malignancy
- B-cell Neoplasm
- Non-Hodgkin Lymphoma
synonyms:
- Waldenström macroglobulinemia
- Waldenstrom's macroglobulinemia
- WM
description: >-
Waldenstrom macroglobulinemia is an indolent B-cell neoplasm defined by bone
marrow infiltration with lymphoplasmacytic lymphoma and secretion of a
monoclonal IgM paraprotein. The disease is driven in most cases by MYD88
L265P and further shaped in a substantial subset by subclonal CXCR4
WHIM-like mutations. Morbidity reflects both marrow infiltration by the
lymphoplasmacytic clone and the downstream effects of the IgM paraprotein,
including hyperviscosity and peripheral neuropathy. Current disease-level
management centers on observation for asymptomatic disease, fixed-duration
chemoimmunotherapy, covalent BTK inhibition, and plasmapheresis for urgent
paraprotein reduction.
disease_term:
preferred_term: Waldenstrom macroglobulinemia
term:
id: MONDO:0100280
label: Waldenstrom macroglobulinemia
parents:
- lymphoplasmacytic lymphoma
has_subtypes:
- name: Asymptomatic Waldenstrom Macroglobulinemia
classification: clinical_course
description: >-
Asymptomatic WM is managed with observation rather than immediate therapy
unless there is critically elevated IgM or compromised hematopoietic
function.
evidence:
- reference: PMID:37099027
reference_title: "Report of consensus panel 1 from the 11(th) International Workshop on Waldenstrom's Macroglobulinemia on management of symptomatic, treatment-naïve patients."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
The panel reiterated that watchful waiting remains the gold standard for
asymptomatic patients without critically elevated IgM or compromised
hematopoietic function.
explanation: >-
This consensus update supports asymptomatic WM as a clinically meaningful
disease-course subtype defined by deferred treatment.
- name: Symptomatic Waldenstrom Macroglobulinemia
classification: clinical_course
description: >-
Symptomatic WM is the treatment-requiring clinical subset distinguished from
asymptomatic WM and precursor IgM-related states.
evidence:
- reference: PMID:12720118
reference_title: "Clinicopathological definition of Waldenstrom's macroglobulinemia: consensus panel recommendations from the Second International Workshop on Waldenstrom's Macroglobulinemia."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
Simple criteria to distinguish patients with symptomatic WM who require
therapy from those with asymptomatic WM and MGUS were also proposed.
explanation: >-
This consensus definition supports symptomatic WM as a clinically distinct
treatment-triggering subtype axis within the same disease entry.
- name: MYD88-mutant Waldenstrom Macroglobulinemia
classification: molecular
description: >-
The dominant molecular subset of WM carries MYD88 L265P, an early oncogenic
lesion that organizes the baseline disease program.
genes:
- preferred_term: MYD88
term:
id: hgnc:7562
label: MYD88
evidence:
- reference: PMID:24224040
reference_title: "L265P mutation of the MYD88 gene is frequent in Waldenström's macroglobulinemia and its absence in myeloma."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
These results suggest that the L265P mutation is involved in the majority
of Waldenström's macroglobulinemia.
explanation: >-
This supports a MYD88-mutant molecular subset that belongs inside the same
disease page rather than as a separate dismech entry.
- name: CXCR4-mutated Waldenstrom Macroglobulinemia
classification: molecular
description: >-
A treatment-relevant molecular subset of WM acquires subclonal WHIM-like
CXCR4 mutations layered onto the core disease program.
genes:
- preferred_term: CXCR4
term:
id: hgnc:2561
label: CXCR4
evidence:
- reference: PMID:26659815
reference_title: "Clonal architecture of CXCR4 WHIM-like mutations in Waldenström Macroglobulinaemia."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The findings show that CXCR4(WHIM) mutations are more common in WM than
previously revealed, and are primarily subclonal, supporting their
acquisition after MYD88(L265P) in WM oncogenesis.
explanation: >-
This supports CXCR4-mutated WM as a molecular facet subtype nested within
the broader Waldenstrom disease graph.
definitions:
- name: Pathologic definition of Waldenstrom macroglobulinemia
definition_type: CASE_DEFINITION
description: >-
Waldenstrom macroglobulinemia is a distinct clinicopathologic entity defined
by bone marrow infiltration by lymphoplasmacytic lymphoma together with an
IgM monoclonal gammopathy.
scope: General clinicopathologic definition for disease-level curation
evidence:
- reference: PMID:12720118
reference_title: "Clinicopathological definition of Waldenstrom's macroglobulinemia: consensus panel recommendations from the Second International Workshop on Waldenstrom's Macroglobulinemia."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
WM is an uncommon lymphoproliferative disorder characterized primarily by
bone marrow infiltration and IgM monoclonal gammopathy.
explanation: >-
This consensus definition anchors WM as a disease entity defined by marrow
lymphoplasmacytic infiltration together with IgM paraproteinemia.
pathophysiology:
- name: Bone Marrow Lymphoplasmacytic Infiltration
description: >-
The disease-defining tissue state is infiltration of the bone marrow by a
clonal lymphoplasmacytic population spanning mature B-cell, plasmacytoid,
and plasma-cell differentiation states.
evidence:
- reference: PMID:12720118
reference_title: "Clinicopathological definition of Waldenstrom's macroglobulinemia: consensus panel recommendations from the Second International Workshop on Waldenstrom's Macroglobulinemia."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
WM is an uncommon lymphoproliferative disorder characterized primarily by
bone marrow infiltration and IgM monoclonal gammopathy.
explanation: >-
The consensus definition identifies marrow infiltration as a primary
clinicopathologic feature of WM.
- reference: PMID:11718214
reference_title: "Lymphoplasmacytic lymphoma/immunocytoma: towards a disease-targeted treatment?"
supports: SUPPORT
evidence_source: OTHER
snippet: >-
Lymphoplasmacytic-lymphoplasmacytoid lymphoma (LPL)/Waldenstrom's
macroglobulinemia (WM) or immunocytoma (IMC) consists of diffuse
proliferation of small mature B lymphocytes, plasmacytoid lymphocytes, and
plasma-cells.
explanation: >-
This abstract specifies the marrow-infiltrating tumor-cell composition
that underlies the lymphoplasmacytic clone in WM.
cell_types:
- preferred_term: B cell
term:
id: CL:0000236
label: B cell
- preferred_term: plasma cell
term:
id: CL:0000786
label: plasma cell
biological_processes:
- preferred_term: cell population proliferation
modifier: INCREASED
term:
id: GO:0008283
label: cell population proliferation
locations:
- preferred_term: bone marrow
term:
id: UBERON:0002371
label: bone marrow
downstream:
- target: Monoclonal IgM Secretion
description: The marrow lymphoplasmacytic clone gives rise to the circulating IgM paraprotein.
evidence:
- reference: PMID:12720118
reference_title: "Clinicopathological definition of Waldenstrom's macroglobulinemia: consensus panel recommendations from the Second International Workshop on Waldenstrom's Macroglobulinemia."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
WM is an uncommon lymphoproliferative disorder characterized primarily by
bone marrow infiltration and IgM monoclonal gammopathy.
explanation: >-
This consensus definition supports the causal pairing of marrow
lymphoplasmacytic disease with its defining IgM paraprotein output.
- name: Monoclonal IgM Secretion
description: >-
The clonal lymphoplasmacytic population produces a monoclonal IgM
paraprotein that accumulates in the circulation and mediates important
downstream complications.
evidence:
- reference: PMID:12720118
reference_title: "Clinicopathological definition of Waldenstrom's macroglobulinemia: consensus panel recommendations from the Second International Workshop on Waldenstrom's Macroglobulinemia."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
WM is an uncommon lymphoproliferative disorder characterized primarily by
bone marrow infiltration and IgM monoclonal gammopathy.
explanation: >-
The consensus definition supports monoclonal IgM production as a core
downstream output of the malignant lymphoplasmacytic clone.
cell_types:
- preferred_term: IgM plasma cell
term:
id: CL:0000986
label: IgM plasma cell
biological_processes:
- preferred_term: immunoglobulin production
modifier: INCREASED
term:
id: GO:0002377
label: immunoglobulin production
locations:
- preferred_term: blood serum
term:
id: UBERON:0001977
label: blood serum
downstream:
- target: Serum Hyperviscosity
description: Heavy circulating IgM burden increases serum viscosity and contributes to neurologic complications.
evidence:
- reference: PMID:18813229
reference_title: "Neurological manifestations of Waldenström macroglobulinemia."
supports: PARTIAL
evidence_source: HUMAN_CLINICAL
snippet: >-
Peripheral neuropathy occurs in nearly half of patients with this
condition, and hyperviscosity-related nervous system disorders are
encountered in up to a third.
explanation: >-
This clinical review directly documents hyperviscosity-related neurologic
complications in WM; coupled with the disease-defining IgM paraprotein,
it supports serum hyperviscosity as a downstream pathogenic process.
- name: Serum Hyperviscosity
description: >-
High circulating IgM burden increases serum viscosity and contributes to
neurologic morbidity in a substantial subset of patients.
evidence:
- reference: PMID:18813229
reference_title: "Neurological manifestations of Waldenström macroglobulinemia."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
Peripheral neuropathy occurs in nearly half of patients with this
condition, and hyperviscosity-related nervous system disorders are
encountered in up to a third.
explanation: >-
This review supports serum hyperviscosity as a common intermediate
pathogenic process contributing to WM neurologic morbidity.
locations:
- preferred_term: blood
term:
id: UBERON:0000178
label: blood
- name: MYD88 L265P Founder Mutation
description: >-
MYD88 L265P is the dominant recurrent somatic lesion in WM and functions as
an early oncogenic event in disease pathogenesis.
evidence:
- reference: PMID:24224040
reference_title: "L265P mutation of the MYD88 gene is frequent in Waldenström's macroglobulinemia and its absence in myeloma."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
These results suggest that the L265P mutation is involved in the majority
of Waldenström's macroglobulinemia.
explanation: >-
This patient-series abstract supports MYD88 L265P as a major recurrent
driver lesion in WM.
downstream:
- target: Bone Marrow Lymphoplasmacytic Infiltration
description: MYD88-mutant clones participate in the core lymphoplasmacytic marrow disease state.
evidence:
- reference: PMID:24224040
reference_title: "L265P mutation of the MYD88 gene is frequent in Waldenström's macroglobulinemia and its absence in myeloma."
supports: PARTIAL
evidence_source: HUMAN_CLINICAL
snippet: >-
These results suggest that the L265P mutation is involved in the majority
of Waldenström's macroglobulinemia.
explanation: >-
This supports MYD88 L265P as a founding lesion contributing to the core
marrow lymphoplasmacytic disease state.
- target: CXCR4 WHIM-like Subclonal Mutation
description: Secondary CXCR4 mutations are commonly acquired after the MYD88 founder event.
evidence:
- reference: PMID:26659815
reference_title: "Clonal architecture of CXCR4 WHIM-like mutations in Waldenström Macroglobulinaemia."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The findings show that CXCR4(WHIM) mutations are more common in WM than
previously revealed, and are primarily subclonal, supporting their
acquisition after MYD88(L265P) in WM oncogenesis.
explanation: >-
This directly supports CXCR4 mutation acquisition as a later subclonal
branch layered onto the MYD88-mutant WM clone.
- name: CXCR4 WHIM-like Subclonal Mutation
description: >-
A substantial subset of WM cases acquire subclonal WHIM-like CXCR4
mutations, adding heterogeneity to the MYD88-mutant clone and influencing
treatment response.
evidence:
- reference: PMID:26659815
reference_title: "Clonal architecture of CXCR4 WHIM-like mutations in Waldenström Macroglobulinaemia."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
By combined AS-PCR and Sanger sequencing, CXCR4(WHIM) mutations were
identified in 44/102 (43%), 21/62 (34%), 2/12 (17%) and 1/20 (5%) untreated
WM, previously treated WM, IgM MGUS and marginal zone lymphoma patients,
respectively, but no chronic lymphocytic leukaemia, multiple myeloma,
non-IgM MGUS patients or healthy donors.
explanation: >-
This supports CXCR4 WHIM-like mutation as a recurrent, disease-enriched
secondary genomic event in WM.
- name: Mast Cell Supportive Signaling
description: >-
Excess marrow mast cells provide trophic and survival signals to the
lymphoplasmacytic clone, making the marrow microenvironment an active
participant in WM pathogenesis.
evidence:
- reference: PMID:18216294
reference_title: "CD27-CD70 interactions in the pathogenesis of Waldenstrom macroglobulinemia."
supports: SUPPORT
evidence_source: IN_VITRO
snippet: >-
Importantly, sCD27 stimulated expression of CD40L on 10 of 10 BM MC
samples and APRIL on 4 of 10 BM MC samples obtained from patients with WM
as well as on LAD2 MCs.
explanation: >-
This experiment supports a mechanistic microenvironment program in which
WM-associated mast cells are induced to express trophic ligands.
- reference: PMID:18216294
reference_title: "CD27-CD70 interactions in the pathogenesis of Waldenstrom macroglobulinemia."
supports: SUPPORT
evidence_source: MODEL_ORGANISM
snippet: >-
Last, treatment of severe combined immunodeficiency-human (SCID-hu) mice
with established WM using the SGN-70 antibody blocked disease progression
in 12 of 12 mice, whereas disease progressed in all 5 untreated mice.
explanation: >-
This xenograft result supports the biologic importance of the CD27-CD70
microenvironment axis in sustaining WM disease progression.
cell_types:
- preferred_term: mast cell
term:
id: CL:0000097
label: mast cell
- preferred_term: B cell
term:
id: CL:0000236
label: B cell
biological_processes:
- preferred_term: cell-cell signaling
term:
id: GO:0007267
label: cell-cell signaling
locations:
- preferred_term: bone marrow
term:
id: UBERON:0002371
label: bone marrow
downstream:
- target: Bone Marrow Lymphoplasmacytic Infiltration
description: Microenvironmental mast-cell signals support persistence of the malignant lymphoplasmacytic clone.
evidence:
- reference: PMID:18216294
reference_title: "CD27-CD70 interactions in the pathogenesis of Waldenstrom macroglobulinemia."
supports: PARTIAL
evidence_source: MODEL_ORGANISM
snippet: >-
Last, treatment of severe combined immunodeficiency-human (SCID-hu) mice
with established WM using the SGN-70 antibody blocked disease progression
in 12 of 12 mice, whereas disease progressed in all 5 untreated mice.
explanation: >-
Interrupting the mast-cell linked CD27-CD70 signaling axis reduced WM
progression in vivo, partially supporting this pathway as an upstream
contributor to persistence of the lymphoplasmacytic clone.
histopathology:
- name: Lymphoplasmacytic Lymphoma
finding_term:
preferred_term: Lymphoplasmacytic Lymphoma
term:
id: NCIT:C3212
label: Lymphoplasmacytic Lymphoma
frequency: OBLIGATE
diagnostic: true
description: >-
The defining pathologic diagnosis in WM is lymphoplasmacytic lymphoma in the
bone marrow, typically with an intertrabecular infiltrative pattern.
evidence:
- reference: PMID:12720118
reference_title: "Clinicopathological definition of Waldenstrom's macroglobulinemia: consensus panel recommendations from the Second International Workshop on Waldenstrom's Macroglobulinemia."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
The underlying pathological diagnosis in WM is lymphoplasmacytic lymphoma
as defined by the World Health Organization (WHO) and Revised
European-American Lymphoma (REAL) classification criteria.
explanation: >-
Because the consensus definition states that the underlying pathologic
diagnosis in WM is lymphoplasmacytic lymphoma, this histopathologic finding
is OBLIGATE for the disease concept curated here.
phenotypes:
- category: Hematologic
name: IgM Paraproteinemia
frequency: OBLIGATE
diagnostic: true
description: >-
A monoclonal IgM paraprotein is required for the disease concept curated
here and reflects secretion by the lymphoplasmacytic clone.
phenotype_term:
preferred_term: IgM heavy chain paraproteinemia
term:
id: HP:0020196
label: IgM heavy chain paraproteinemia
evidence:
- reference: PMID:12720118
reference_title: "Clinicopathological definition of Waldenstrom's macroglobulinemia: consensus panel recommendations from the Second International Workshop on Waldenstrom's Macroglobulinemia."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
WM is an uncommon lymphoproliferative disorder characterized primarily by
bone marrow infiltration and IgM monoclonal gammopathy.
explanation: >-
The consensus definition makes IgM monoclonal gammopathy part of the
defining disease concept, supporting an OBLIGATE IgM paraproteinemia
phenotype.
- category: Lymphatic
name: Lymphadenopathy
description: >-
Diffuse lymphadenopathy is a common manifestation of tissue involvement by
the lymphoplasmacytic clone.
phenotype_term:
preferred_term: Lymphadenopathy
term:
id: HP:0002716
label: Lymphadenopathy
evidence:
- reference: PMID:18813229
reference_title: "Neurological manifestations of Waldenström macroglobulinemia."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
Waldenström macroglobulinemia, a condition that most commonly occurs in
lymphoplasmacytic lymphoma, typically manifests with diffuse
lymphadenopathies, cytopenias, and a markedly elevated erythrocyte
sedimentation rate.
explanation: >-
This review directly lists diffuse lymphadenopathy among the typical WM
clinical manifestations.
- category: Neurologic
name: Peripheral Neuropathy
frequency: FREQUENT
description: >-
Peripheral neuropathy is a major symptomatic complication of WM and often
reflects the downstream consequences of the circulating IgM paraprotein.
phenotype_term:
preferred_term: Peripheral neuropathy
term:
id: HP:0009830
label: Peripheral neuropathy
evidence:
- reference: PMID:18813229
reference_title: "Neurological manifestations of Waldenström macroglobulinemia."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
Peripheral neuropathy occurs in nearly half of patients with this
condition, and hyperviscosity-related nervous system disorders are
encountered in up to a third.
explanation: >-
Nearly half of patients corresponds to about 50%, which falls in the
FREQUENT band (30-79%).
genetic:
- name: MYD88
association: Somatic Mutation
notes: >-
MYD88 L265P is the dominant recurrent somatic lesion in WM and is treated
here as an upstream founder event in disease oncogenesis.
evidence:
- reference: PMID:24224040
reference_title: "L265P mutation of the MYD88 gene is frequent in Waldenström's macroglobulinemia and its absence in myeloma."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
These results suggest that the L265P mutation is involved in the majority
of Waldenström's macroglobulinemia.
explanation: >-
This supports MYD88 L265P as the dominant recurrent somatic alteration in WM.
- name: CXCR4
association: Somatic Mutation
notes: >-
WHIM-like CXCR4 mutations occur in a substantial subset of WM cases and are
primarily subclonal, consistent with later acquisition after MYD88.
evidence:
- reference: PMID:26659815
reference_title: "Clonal architecture of CXCR4 WHIM-like mutations in Waldenström Macroglobulinaemia."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The findings show that CXCR4(WHIM) mutations are more common in WM than
previously revealed, and are primarily subclonal, supporting their
acquisition after MYD88(L265P) in WM oncogenesis.
explanation: >-
This supports CXCR4 mutation as a recurrent secondary somatic event in WM.
treatments:
- name: Watchful Waiting
description: >-
Observation without immediate therapy is the standard disease-management
strategy for asymptomatic WM without critically elevated IgM or compromised
hematopoietic function.
treatment_term:
preferred_term: watchful waiting
term:
id: MAXO:0000950
label: supportive care
evidence:
- reference: PMID:37099027
reference_title: "Report of consensus panel 1 from the 11(th) International Workshop on Waldenstrom's Macroglobulinemia on management of symptomatic, treatment-naïve patients."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
The panel reiterated that watchful waiting remains the gold standard for
asymptomatic patients without critically elevated IgM or compromised
hematopoietic function.
explanation: >-
This consensus update supports watchful waiting as the standard management
approach for asymptomatic WM.
- name: Bendamustine-Rituximab
description: >-
Fixed-duration bendamustine-rituximab chemoimmunotherapy remains a central
first-line option for symptomatic treatment-naive WM.
treatment_term:
preferred_term: immunotherapy
term:
id: NCIT:C15262
label: Immunotherapy
therapeutic_agent:
- preferred_term: bendamustine
term:
id: CHEBI:135515
label: bendamustine
- preferred_term: rituximab
term:
id: NCIT:C1702
label: Rituximab
evidence:
- reference: PMID:37099027
reference_title: "Report of consensus panel 1 from the 11(th) International Workshop on Waldenstrom's Macroglobulinemia on management of symptomatic, treatment-naïve patients."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
For first-line treatment, chemoimmunotherapy (CIT) regimens such as
dexamethasone, cyclophosphamide, rituximab (DRC), or bendamustine,
rituximab (Benda-R) continue to play a central role in managing WM, as
they are effective, of fixed duration, generally well-tolerated, and
affordable.
explanation: >-
The 2023 IWWM consensus panel identifies bendamustine-rituximab as a
central fixed-duration first-line treatment option for symptomatic WM.
- name: Zanubrutinib
description: >-
Zanubrutinib is a covalent BTK inhibitor option for symptomatic WM and shows
lower toxicity and deeper remissions than ibrutinib in the cited randomized
trial update.
treatment_term:
preferred_term: targeted therapy
term:
id: NCIT:C93352
label: Targeted Therapy
therapeutic_agent:
- preferred_term: zanubrutinib
term:
id: NCIT:C141428
label: Zanubrutinib
evidence:
- reference: PMID:37099027
reference_title: "Report of consensus panel 1 from the 11(th) International Workshop on Waldenstrom's Macroglobulinemia on management of symptomatic, treatment-naïve patients."
supports: SUPPORT
evidence_source: OTHER
snippet: >-
In a Phase III randomized trial updated at IWWM-11, the second-generation
cBTKi, zanubrutinib, was less toxic than ibrutinib and induced deeper
remissions, thus categorizing zanubrutinib as a suitable treatment option
in WM.
explanation: >-
This consensus update supports zanubrutinib as an evidence-based BTK
inhibitor option for WM, with favorable efficacy and tolerability.
- name: Plasmapheresis
description: >-
Plasmapheresis is used for rapid paraprotein reduction in hyperviscosity and
related neurologic complications while systemic therapy addresses the
underlying clone.
treatment_term:
preferred_term: plasmapheresis
term:
id: NCIT:C15304
label: Plasmapheresis
evidence:
- reference: PMID:18813229
reference_title: "Neurological manifestations of Waldenström macroglobulinemia."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
Treatment options, which should address both the paraprotein burden and
the lymphoplasmacytic clone, include plasmapheresis and chemotherapy with
alkylating agents, nucleoside analogs, and rituximab.
explanation: >-
This review supports plasmapheresis as a disease-relevant intervention for
rapid reduction of pathogenic paraprotein burden in WM.
mappings:
mondo_mappings:
- term:
id: MONDO:0100280
label: Waldenstrom macroglobulinemia
mapping_predicate: skos:exactMatch
mapping_source: MONDO
mapping_justification: Primary MONDO disease identifier for this Waldenstrom macroglobulinemia entry.
Waldenstrom macroglobulinemia (WM) is best modeled here as a single disease-level mechanism graph rooted to MONDO:0100280 Waldenstrom macroglobulinemia, not as a lattice of every oncology subclass. The key defining combination is:
Following issue #1198, I treated lymphoplasmacytic lymphoma as the disease
parent / diagnostic histopathology concept rather than opening a separate dismech
page for every related ontology refinement. Likewise, I did not split
smoldering WM, familial WM, refractory WM, recurrent WM, or transformed WM into
separate disorder files, because those are disease-state, predisposition, or
transformation facets rather than distinct causal programs for the baseline WM
mechanism graph. In the YAML, this was reflected by keeping one disease page and
encoding subtype structure only as flat has_subtypes facets for clinical
course and molecular context.
Relevant ontology anchors:
PMID:12720118 remains the key disease-definition paper for this curation. It defines WM as an uncommon lymphoproliferative disorder characterized by bone marrow lymphoplasmacytic infiltration and IgM monoclonal gammopathy, and it explicitly argues that WM is a distinct clinicopathologic entity rather than just an IgM secretion syndrome.
PMID:11718214 complements this by describing the underlying cell composition: small mature B lymphocytes, plasmacytoid lymphocytes, and plasma cells. For the dismech entry, that supports treating the bone-marrow lymphoplasmacytic clone as the core disease unit and the IgM paraprotein as a downstream biochemical output of that clone.
This is the disease-defining tissue state. The mechanistic unit is the marrow infiltrating clone composed of B-cell/plasma-cell lineage lymphoplasmacytic cells. This node should sit near the top of the graph because it links the founding genomic lesions to the clinical consequences of marrow occupation and paraprotein secretion.
Key support:
The IgM paraprotein is the key biochemical output of the malignant clone and is best modeled as a separate downstream node rather than bundled into the marrow infiltration node. This helps keep the graph atomic and allows direct edges to paraprotein-driven complications.
Key support:
Hyperviscosity is a downstream biophysical consequence of heavy circulating IgM burden. I modeled this as a separate pathophysiology node rather than collapsing it into the phenotype list, because it is an intermediate pathogenic process that explains neurologic and visual symptoms.
Key support:
MYD88 L265P is the dominant recurrent somatic lesion in WM and should be treated as an upstream genomic driver node. The cached abstract set supports two important, conservative claims:
Because the cached abstract set was used conservatively, I did not overstate the full MYD88 -> BTK -> IRAK -> NF-kB signaling chain in the YAML evidence block without a validated PMID cache line for that exact claim. That mechanistic detail is real and well-supported in the broader WM literature, but the YAML entry is restricted to what could be quoted exactly and validated in this branch.
CXCR4 mutations are not the founding lesion; they are modeled as a later, subclonal branch layered onto the MYD88-mutant clone. This is a good example of an oncology refinement that belongs inside the same disease graph rather than in a separate disease page.
Key support:
PMID:18216294 shows that excess marrow mast cells are common in WM and provide growth/survival signals to lymphoplasmacytic cells. This is worth a separate node because it captures a bona fide microenvironmental mechanism rather than a mere descriptive pathology feature.
Key support:
The best abstract-backed phenotype set from the cached reference slice is:
Hyperviscosity-related neurologic disorders are common enough to matter mechanistically but were better represented as a downstream pathophysiology node than as an HP-grounded phenotype because the available ontology grounding in this schema is much cleaner for the manifestations than for the syndrome label itself.
The current disease-level treatment section should emphasize:
Following #1198, NCIT should be preferred where it gives materially better oncology specificity. In the YAML this means:
I initially attempted to ground BR and zanubrutinib with NCIT regimen terms as
well, but the current RegimenTerm validator expansion in this branch did not
accept those codes, so I retained the validated disease-level treatment
representation using treatment actions plus ontology-grounded agents/procedures.