Ask OpenScientist

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

Submitting...

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

0
Mappings
0
Definitions
0
Inheritance
4
Pathophysiology
1
Histopathology
29
Phenotypes
4
Pathograph
8
Genes
7
Treatments
0
Subtypes
0
Differentials
0
Datasets
0
Trials
0
Models
20
References
1
Deep Research
🏷

Classifications

Harrison's Chapter
cancer hematologic malignancy
ICD-O Morphology
Leukemia

Pathophysiology

4
JAK-STAT Pathway Hyperactivation
Driver mutations in JAK2, CALR, or MPL all converge on constitutive activation of JAK-STAT signaling. JAK2 V617F directly activates the kinase; CALR and MPL mutations lead to activation of MPL receptor signaling.
megakaryocyte link hematopoietic stem cell link
JAK-STAT signaling pathway link ↑ INCREASED
bone marrow link
Abnormal Megakaryopoiesis
Driver mutations cause aberrant megakaryocyte proliferation and maturation. Megakaryocytes show characteristic atypia with clustering, abnormal lobation, and defective platelet production.
megakaryocyte differentiation link ⚠ ABNORMAL
Cytokine-Mediated Marrow Fibrosis
Atypical megakaryocytes release profibrotic cytokines including TGF-beta, PDGF, and bFGF, stimulating marrow stromal cells to deposit reticulin and collagen fibers. Progressive fibrosis replaces normal hematopoietic tissue.
extracellular matrix organization link ↑ INCREASED
Show evidence (1 reference)
PMID:41514563 PARTIAL
"Primary myelofibrosis (PMF) is a Philadelphia chromosome (Ph)-negative myeloproliferative neoplasm (MPN) that features clonal proliferation of atypical megakaryocytes and myeloid cells, fibrosis of the bone marrow, extramedullary hematopoiesis, and increased risk of leukemic transformation to..."
This abstract highlights bone marrow fibrosis and atypical megakaryocyte proliferation, supporting the fibrosis mechanism described.
Extramedullary Hematopoiesis
As bone marrow function declines due to fibrosis, hematopoiesis shifts to spleen, liver, and other sites. This causes massive splenomegaly and hepatomegaly with associated symptoms.
hematopoiesis link ⚠ ABNORMAL
spleen link

Histopathology

1
Bone Marrow Fibrosis VERY_FREQUENT
Primary myelofibrosis is characterized by bone marrow fibrosis.
Show evidence (1 reference)
PMID:33477816 PARTIAL
"Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by"
Abstract describes PMF as a myeloproliferative neoplasm characterized by bone marrow fibrosis.

Pathograph

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

Phenotypes

29
Blood 9
Anemia FREQUENT Anemia (HP:0001903)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0001903 | Anemia | Frequent (79-30%)"
Orphanet classifies anemia as frequent (79-30%) in primary myelofibrosis.
PMID:36332787 SUPPORT Human Clinical
"Clinical manifestations of MF include splenomegaly, constitutional symptoms, and anemia, whose pathogenesis is multifactorial and largely due to ineffective erythropoiesis and is clinically associated with poor quality of life and reduced overall survival."
Review confirms anemia as a key clinical manifestation with multifactorial pathogenesis.
Thrombocytopenia FREQUENT Thrombocytopenia (HP:0001873)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0001873 | Thrombocytopenia | Frequent (79-30%)"
Orphanet classifies thrombocytopenia as frequent (79-30%) in primary myelofibrosis.
Pancytopenia OCCASIONAL Pancytopenia (HP:0001876)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0001876 | Pancytopenia | Occasional (29-5%)"
Orphanet classifies pancytopenia as occasional (29-5%) in primary myelofibrosis.
Thrombocytosis OCCASIONAL Thrombocytosis (HP:0001894)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0001894 | Thrombocytosis | Occasional (29-5%)"
Orphanet classifies thrombocytosis as occasional (29-5%) in primary myelofibrosis.
Leukocytosis OCCASIONAL Increased total leukocyte count (HP:0001974)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0001974 | Leukocytosis | Occasional (29-5%)"
Orphanet classifies leukocytosis as occasional (29-5%) in primary myelofibrosis.
PMID:28808761 SUPPORT Human Clinical
"Minor criteria, include a) anemia not attributed to a comorbid condition, b) leukocytosis ≥ 11 × 109, c) palpable splenomegaly, d) lactate dehydrogenase (LDH) level above normal limit of institutional reference range and e) leukoerythroblastosis"
WHO diagnostic criteria list leukocytosis as a minor criterion for PMF diagnosis.
Extramedullary Hematopoiesis OCCASIONAL Extramedullary hematopoiesis (HP:0001978)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0001978 | Extramedullary hematopoiesis | Occasional (29-5%)"
Orphanet classifies extramedullary hematopoiesis as occasional (29-5%) in primary myelofibrosis.
PMID:33197049 SUPPORT Human Clinical
"Additional disease features include bone marrow reticulin/collagen fibrosis, aberrant inflammatory cytokine expression, anemia, hepatosplenomegaly, extramedullary hematopoiesis (EMH), constitutional symptoms, cachexia, leukemic progression, and shortened survival."
Tefferi 2021 review lists extramedullary hematopoiesis as a core disease feature of PMF.
Abnormal Bleeding OCCASIONAL Abnormal bleeding (HP:0001892)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0001892 | Abnormal bleeding | Occasional (29-5%)"
Orphanet classifies abnormal bleeding as occasional (29-5%) in primary myelofibrosis.
PMID:28808761 SUPPORT Human Clinical
"Bleeding and thrombosis are long recognized complications of myelofibrosis (MF) and contribute significantly to its morbidity and mortality."
Review confirms bleeding as a recognized complication contributing to MF morbidity and mortality.
Petechiae OCCASIONAL Petechiae (HP:0000967)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0000967 | Petechiae | Occasional (29-5%)"
Orphanet classifies petechiae as occasional (29-5%) in primary myelofibrosis.
Purpura OCCASIONAL Purpura (HP:0000979)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0000979 | Purpura | Occasional (29-5%)"
Orphanet classifies purpura as occasional (29-5%) in primary myelofibrosis.
Cardiovascular 4
Splenomegaly FREQUENT Splenomegaly (HP:0001744)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0001744 | Splenomegaly | Frequent (79-30%)"
Orphanet classifies splenomegaly as frequent (79-30%) in primary myelofibrosis.
PMID:33197049 SUPPORT Human Clinical
"for symptomatic splenomegaly, hydroxyurea and ruxolitinib"
Tefferi 2021 review identifies symptomatic splenomegaly as a major clinical feature requiring treatment.
Hepatosplenomegaly FREQUENT Hepatosplenomegaly (HP:0001433)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0001433 | Hepatosplenomegaly | Frequent (79-30%)"
Orphanet classifies hepatosplenomegaly as frequent (79-30%) in primary myelofibrosis.
PMID:33197049 SUPPORT Human Clinical
"Additional disease features include bone marrow reticulin/collagen fibrosis, aberrant inflammatory cytokine expression, anemia, hepatosplenomegaly, extramedullary hematopoiesis (EMH), constitutional symptoms, cachexia, leukemic progression, and shortened survival."
Tefferi 2021 review lists hepatosplenomegaly as a core disease feature.
Portal Hypertension OCCASIONAL Portal hypertension (HP:0001409)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0001409 | Portal hypertension | Occasional (29-5%)"
Orphanet classifies portal hypertension as occasional (29-5%) in primary myelofibrosis.
PMID:25755427 SUPPORT Human Clinical
"Portal hypertension is found in up to 7% of patients."
Reports portal hypertension frequency of up to 7% in myeloproliferative disease patients.
Lymphadenopathy OCCASIONAL Lymphadenopathy (HP:0002716)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0002716 | Lymphadenopathy | Occasional (29-5%)"
Orphanet classifies lymphadenopathy as occasional (29-5%) in primary myelofibrosis.
Digestive 2
Hepatomegaly FREQUENT Hepatomegaly (HP:0002240)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0002240 | Hepatomegaly | Frequent (79-30%)"
Orphanet classifies hepatomegaly as frequent (79-30%) in primary myelofibrosis.
Anorexia OCCASIONAL Anorexia (HP:0002039)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0002039 | Anorexia | Occasional (29-5%)"
Orphanet classifies anorexia as occasional (29-5%) in primary myelofibrosis.
Integument 1
Pallor FREQUENT Pallor (HP:0000980)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0000980 | Pallor | Frequent (79-30%)"
Orphanet classifies pallor as frequent (79-30%) in primary myelofibrosis.
Metabolism 1
Fever OCCASIONAL Fever (HP:0001945)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0001945 | Fever | Occasional (29-5%)"
Orphanet classifies fever as occasional (29-5%) in primary myelofibrosis.
PMID:32300883 SUPPORT Human Clinical
"Philadelphia-negative myeloproliferative neoplasms (MPNs), essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF), are rare clonal hematopoietic stem cell disorders accompanied by a strong inflammatory milieu, which is directly responsible for constitutional symptoms..."
Confirms fever as a constitutional symptom directly caused by the inflammatory milieu in MPN including myelofibrosis.
Constitutional 2
Fatigue FREQUENT Fatigue (HP:0012378)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0012378 | Fatigue | Frequent (79-30%)"
Orphanet classifies fatigue as frequent (79-30%) in primary myelofibrosis.
PMID:28808761 SUPPORT Human Clinical
"Clinical manifestations of MF include cytopenia, fatigue and constitutional symptoms such as low-grade fever, weight loss and night sweats."
Review identifies fatigue as a primary clinical manifestation of myelofibrosis.
Flank Pain OCCASIONAL Flank pain (HP:0030157)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0030157 | Flank pain | Occasional (29-5%)"
Orphanet classifies flank pain as occasional (29-5%) in primary myelofibrosis.
Other 10
Cachexia VERY_RARE Cachexia (HP:0004326)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0004326 | Cachexia | Very rare (<4-1%)"
Orphanet classifies cachexia as very rare in primary myelofibrosis.
PMID:33197049 SUPPORT Human Clinical
"Additional disease features include bone marrow reticulin/collagen fibrosis, aberrant inflammatory cytokine expression, anemia, hepatosplenomegaly, extramedullary hematopoiesis (EMH), constitutional symptoms, cachexia, leukemic progression, and shortened survival."
Tefferi 2021 review lists cachexia as a recognized disease feature of PMF.
Abnormal Megakaryocyte Morphology FREQUENT Abnormal megakaryocyte morphology (HP:0012143)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0012143 | Abnormal megakaryocyte morphology | Frequent (79-30%)"
Orphanet classifies abnormal megakaryocyte morphology as frequent (79-30%) in primary myelofibrosis.
PMID:41514563 SUPPORT Human Clinical
"Primary myelofibrosis (PMF) is a Philadelphia chromosome (Ph)-negative myeloproliferative neoplasm (MPN) that features clonal proliferation of atypical megakaryocytes and myeloid cells, fibrosis of the bone marrow, extramedullary hematopoiesis, and increased risk of leukemic transformation to..."
Review highlights atypical megakaryocyte proliferation as a defining feature of PMF.
Abnormal Bone Marrow Cell Morphology VERY_FREQUENT Abnormal bone marrow cell morphology (HP:0005561)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0005561 | Abnormality of bone marrow cell morphology | Very frequent (99-80%)"
Orphanet classifies abnormality of bone marrow cell morphology as very frequent (99-80%) in primary myelofibrosis.
Low-Grade Fever OCCASIONAL Low-grade fever (HP:0011134)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0011134 | Low-grade fever | Occasional (29-5%)"
Orphanet classifies low-grade fever as occasional (29-5%) in primary myelofibrosis.
PMID:28808761 SUPPORT Human Clinical
"Clinical manifestations of MF include cytopenia, fatigue and constitutional symptoms such as low-grade fever, weight loss and night sweats."
Review identifies low-grade fever as one of the constitutional symptoms of myelofibrosis.
Poikilocytosis OCCASIONAL Poikilocytosis (HP:0004447)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0004447 | Poikilocytosis | Occasional (29-5%)"
Orphanet classifies poikilocytosis as occasional (29-5%) in primary myelofibrosis.
Arterial Thrombosis OCCASIONAL Arterial thrombosis (HP:0004420)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0004420 | Arterial thrombosis | Occasional (29-5%)"
Orphanet classifies arterial thrombosis as occasional (29-5%) in primary myelofibrosis.
PMID:28808761 SUPPORT Human Clinical
"Both arterial and venous thrombotic events are not uncommon in patients with PMF"
Review confirms arterial thrombosis as a recognized complication of PMF.
Venous Thrombosis OCCASIONAL Venous thrombosis (HP:0004936)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0004936 | Venous thrombosis | Occasional (29-5%)"
Orphanet classifies venous thrombosis as occasional (29-5%) in primary myelofibrosis.
PMID:28808761 SUPPORT Human Clinical
"Both arterial and venous thrombotic events are not uncommon in patients with PMF"
Review confirms venous thrombosis as a recognized complication of PMF.
Ecchymosis OCCASIONAL Ecchymosis (HP:0031364)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"HP:0031364 | Ecchymosis | Occasional (29-5%)"
Orphanet classifies ecchymosis as occasional (29-5%) in primary myelofibrosis.
Increased Circulating Lactate Dehydrogenase Concentration VERY_RARE Increased circulating lactate dehydrogenase concentration (HP:0025435)
Orphanet classifies LDH elevation as very rare, but it is a WHO minor diagnostic criterion for PMF. The Orphanet frequency likely reflects population-level reporting rather than clinical prevalence among diagnosed patients, where LDH elevation is common.
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0025435 | Increased circulating lactate dehydrogenase concentration | Very rare (<4-1%)"
Orphanet classifies increased LDH as very rare in primary myelofibrosis.
PMID:28808761 SUPPORT Human Clinical
"Minor criteria, include a) anemia not attributed to a comorbid condition, b) leukocytosis ≥ 11 × 109, c) palpable splenomegaly, d) lactate dehydrogenase (LDH) level above normal limit of institutional reference range and e) leukoerythroblastosis"
LDH above normal is a WHO minor diagnostic criterion for PMF.
Bone Marrow Hypercellularity OCCASIONAL Bone marrow hypercellularity (HP:0031020)
Show evidence (2 references)
ORPHA:824 SUPPORT
"HP:0031020 | Bone marrow hypercellularity | Occasional (29-5%)"
Orphanet classifies bone marrow hypercellularity as occasional (29-5%) in primary myelofibrosis.
PMID:28808761 SUPPORT Human Clinical
"megakaryocytic proliferation and atypia, without reticulin fibrosis > grade 1, accompanied by increased age-adjusted bone marrow (BM) cellularity, granulocytic proliferation, and often decreased erythropoiesis"
WHO diagnostic criteria for prefibrotic PMF include increased age-adjusted bone marrow cellularity.
🧬

Genetic Associations

8
JAK2 (Somatic Activating Mutations)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"JAK2 | Janus kinase 2 | hgnc:6192 | Disease-causing somatic mutation(s) in"
Orphanet confirms JAK2 as harboring disease-causing somatic mutations in PMF.
CALR (Somatic Frameshift Mutations)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"CALR | calreticulin | hgnc:1455 | Disease-causing somatic mutation(s) in"
Orphanet confirms CALR as harboring disease-causing somatic mutations in PMF.
MPL (Somatic Activating Mutations)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"MPL | MPL proto-oncogene, thrombopoietin receptor | hgnc:7217 | Disease-causing somatic mutation(s) in"
Orphanet confirms MPL as harboring disease-causing somatic mutations in PMF.
TET2 (Somatic Loss-of-Function Mutations)
Show evidence (1 reference)
ORPHA:824 SUPPORT
"TET2 | tet methylcytosine dioxygenase 2 | hgnc:25941 | Disease-causing somatic mutation(s) in"
Orphanet lists TET2 as harboring disease-causing somatic mutations in primary myelofibrosis.
ASXL1 (Somatic Loss-of-Function Mutations)
Show evidence (1 reference)
PMID:33197049 SUPPORT Human Clinical
"SRSF2, ASXL1, and U2AF1-Q157 mutations predict inferior survival in PMF, independent of each other and other risk factors."
Tefferi 2021 review confirms ASXL1 as an adverse prognostic mutation in PMF.
EZH2 (Somatic Loss-of-Function Mutations)
SRSF2 (Somatic Mutations)
Show evidence (1 reference)
PMID:33197049 SUPPORT Human Clinical
"SRSF2, ASXL1, and U2AF1-Q157 mutations predict inferior survival in PMF, independent of each other and other risk factors."
Tefferi 2021 review identifies SRSF2 as an adverse prognostic mutation in PMF.
U2AF1 (Somatic Mutations)
Show evidence (1 reference)
PMID:33197049 SUPPORT Human Clinical
"SRSF2, ASXL1, and U2AF1-Q157 mutations predict inferior survival in PMF, independent of each other and other risk factors."
Tefferi 2021 review identifies U2AF1-Q157 as an adverse prognostic mutation in PMF.
💊

Treatments

7
Ruxolitinib
Action: targeted therapy Ontology label: Targeted Therapy NCIT:C93352
Agent: ruxolitinib
JAK1/JAK2 inhibitor approved for intermediate-2 and high-risk PMF. Provides marked reduction in spleen size and constitutional symptoms but does not significantly alter disease course or prevent leukemic transformation.
Fedratinib
Action: targeted therapy Ontology label: Targeted Therapy NCIT:C93352
Agent: fedratinib
JAK2 inhibitor approved for intermediate-2 and high-risk PMF, including patients previously treated with ruxolitinib. Selective JAK2 inhibition with similar efficacy profile.
Allogeneic Stem Cell Transplantation
Action: hematopoietic stem cell transplantation MAXO:0000747
Only potentially curative treatment for PMF. Considered for younger patients with high-risk disease. Significant transplant-related morbidity and mortality must be weighed against disease risk.
Hydroxyurea
Action: chemotherapy Ontology label: cancer chemotherapy MAXO:0000646
Agent: hydroxyurea
Cytoreductive therapy for symptomatic splenomegaly or thrombocytosis. Provides modest benefit but does not address constitutional symptoms as effectively as JAK inhibitors.
Anagrelide
Action: targeted therapy Ontology label: Targeted Therapy NCIT:C93352
Agent: anagrelide
Platelet-lowering agent used for thrombocytosis when present. Selective megakaryocyte inhibitor.
Momelotinib
Action: pharmacotherapy MAXO:0000058
Agent: momelotinib
JAK1/JAK2 and ACVR1/ALK2 inhibitor FDA-approved in 2023 for intermediate- or high-risk PMF with anemia. Uniquely addresses anemia by suppressing hepcidin through ACVR1 inhibition. Demonstrated durable symptom, spleen, and anemia benefits in the MOMENTUM trial.
Show evidence (1 reference)
PMID:37517413 SUPPORT Human Clinical
"Momelotinib was associated with durable symptom, spleen, and anaemia benefits, late responses after week 24, and favourable safety through week 48."
MOMENTUM phase 3 trial demonstrates durable efficacy of momelotinib for symptom, spleen, and anemia endpoints in previously JAK inhibitor-treated MF patients.
Pacritinib
Action: pharmacotherapy MAXO:0000058
Agent: pacritinib
Selective JAK2/IRAK1/ACVR1 inhibitor, JAK1-sparing, FDA-approved in 2022 for PMF with severe thrombocytopenia (platelets less than 50 x 10^9/L). Can be administered at full dose regardless of baseline platelet count.
Show evidence (1 reference)
PMID:35622972 SUPPORT Human Clinical
"the dose finding PAC203 study endorsed the safety and efficacy of 200 mg twice daily, leading to the approval of PAC for the treatment of patients with MF with platelets ≤ 50 × 109/L."
Review of pacritinib development describes its approval for thrombocytopenic MF.
🔬

Biochemical Markers

2
Lactate Dehydrogenase (LDH)
Peripheral Blood Smear
{ }

Source YAML

click to show
name: Primary Myelofibrosis
creation_date: '2026-01-26T02:55:13Z'
updated_date: '2026-05-01T12:00:00Z'
description: >-
  Primary myelofibrosis (PMF) is a clonal myeloproliferative neoplasm characterized
  by bone marrow fibrosis, abnormal megakaryocyte proliferation, extramedullary
  hematopoiesis, and progressive cytopenias. Driver mutations include JAK2 V617F
  (approximately 60%), CALR (25%), and MPL (5%), with 10% being triple-negative.
  Additional mutations in epigenetic regulators (ASXL1, TET2, EZH2) and splicing
  factors contribute to disease heterogeneity and prognosis. PMF causes marked
  splenomegaly, constitutional symptoms, and carries risk of transformation to
  acute myeloid leukemia. JAK inhibitors like ruxolitinib and fedratinib provide
  symptom control, while allogeneic stem cell transplantation remains the only
  curative option.
categories:
- Hematologic Malignancy
- Myeloproliferative Neoplasm
parents:
- myeloproliferative neoplasm
stages:
- name: Prefibrotic PMF
  description: >-
    Early stage characterized by hypercellular marrow with megakaryocyte
    proliferation and atypia, but minimal or absent reticulin fibrosis (grade 0-1).
    Often presents with thrombocytosis and may be mistaken for essential
    thrombocythemia.
- name: Overt PMF
  description: >-
    Advanced stage with significant reticulin or collagen fibrosis (grade 2-3),
    progressive cytopenias, splenomegaly, and constitutional symptoms.
    Leukoerythroblastic blood picture and tear-drop cells are characteristic.
pathophysiology:
- name: JAK-STAT Pathway Hyperactivation
  description: >-
    Driver mutations in JAK2, CALR, or MPL all converge on constitutive activation
    of JAK-STAT signaling. JAK2 V617F directly activates the kinase; CALR and MPL
    mutations lead to activation of MPL receptor signaling.
  cell_types:
  - preferred_term: megakaryocyte
    term:
      id: CL:0000556
      label: megakaryocyte
  - preferred_term: hematopoietic stem cell
    term:
      id: CL:0000037
      label: hematopoietic stem cell
  biological_processes:
  - preferred_term: JAK-STAT signaling pathway
    modifier: INCREASED
    term:
      id: GO:0007259
      label: cell surface receptor signaling pathway via JAK-STAT
  locations:
  - preferred_term: bone marrow
    term:
      id: UBERON:0002371
      label: bone marrow
  downstream:
  - target: Abnormal Megakaryopoiesis
    description: JAK-STAT activation drives megakaryocyte proliferation and atypia
  - target: Cytokine-Mediated Marrow Fibrosis
    description: Activated megakaryocytes release profibrotic cytokines
- name: Abnormal Megakaryopoiesis
  description: >-
    Driver mutations cause aberrant megakaryocyte proliferation and maturation.
    Megakaryocytes show characteristic atypia with clustering, abnormal lobation,
    and defective platelet production.
  biological_processes:
  - preferred_term: megakaryocyte differentiation
    modifier: ABNORMAL
    term:
      id: GO:0030219
      label: megakaryocyte differentiation
- name: Cytokine-Mediated Marrow Fibrosis
  description: >-
    Atypical megakaryocytes release profibrotic cytokines including TGF-beta,
    PDGF, and bFGF, stimulating marrow stromal cells to deposit reticulin and
    collagen fibers. Progressive fibrosis replaces normal hematopoietic tissue.
  evidence:
  - reference: PMID:41514563
    reference_title: "A Review of the Pathological and Molecular Diagnosis of Primary Myelofibrosis."
    supports: PARTIAL
    snippet: "Primary myelofibrosis (PMF) is a Philadelphia chromosome (Ph)-negative myeloproliferative neoplasm (MPN) that features clonal proliferation of atypical megakaryocytes and myeloid cells, fibrosis of the bone marrow, extramedullary hematopoiesis, and increased risk of leukemic transformation to acute myeloid leukemia (AML)."
    explanation: This abstract highlights bone marrow fibrosis and atypical megakaryocyte proliferation, supporting the fibrosis mechanism described.
  biological_processes:
  - preferred_term: extracellular matrix organization
    modifier: INCREASED
    term:
      id: GO:0030198
      label: extracellular matrix organization
  downstream:
  - target: Extramedullary Hematopoiesis
    description: Progressive marrow fibrosis and failure drives hematopoiesis to shift to extramedullary sites
- name: Extramedullary Hematopoiesis
  description: >-
    As bone marrow function declines due to fibrosis, hematopoiesis shifts to
    spleen, liver, and other sites. This causes massive splenomegaly and
    hepatomegaly with associated symptoms.
  locations:
  - preferred_term: spleen
    term:
      id: UBERON:0002106
      label: spleen
  biological_processes:
  - preferred_term: hematopoiesis
    modifier: ABNORMAL
    term:
      id: GO:0030097
      label: hemopoiesis
histopathology:
- name: Bone Marrow Fibrosis
  finding_term:
    preferred_term: Bone Marrow Fibrosis
    term:
      id: NCIT:C36212
      label: Bone Marrow Fibrosis
  frequency: VERY_FREQUENT
  description: Primary myelofibrosis is characterized by bone marrow fibrosis.
  evidence:
  - reference: PMID:33477816
    reference_title: "Focus on Osteosclerotic Progression in Primary Myelofibrosis."
    supports: PARTIAL
    snippet: "Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by"
    explanation: Abstract describes PMF as a myeloproliferative neoplasm characterized by bone marrow fibrosis.

phenotypes:
- category: Abdominal
  name: Splenomegaly
  frequency: FREQUENT
  diagnostic: true
  description: >-
    Massive splenomegaly from extramedullary hematopoiesis is a hallmark of PMF.
    May extend to pelvis causing abdominal discomfort, early satiety, and
    portal hypertension.
  phenotype_term:
    preferred_term: Splenomegaly
    term:
      id: HP:0001744
      label: Splenomegaly
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001744 | Splenomegaly | Frequent (79-30%)"
    explanation: Orphanet classifies splenomegaly as frequent (79-30%) in primary myelofibrosis.
  - reference: PMID:33197049
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "for symptomatic splenomegaly, hydroxyurea and ruxolitinib"
    explanation: Tefferi 2021 review identifies symptomatic splenomegaly as a major clinical feature requiring treatment.
- category: Hematologic
  name: Anemia
  frequency: FREQUENT
  description: >-
    Progressive anemia from bone marrow failure is common. May be multifactorial
    including ineffective erythropoiesis, splenic sequestration, and iron deficiency.
  phenotype_term:
    preferred_term: Anemia
    term:
      id: HP:0001903
      label: Anemia
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001903 | Anemia | Frequent (79-30%)"
    explanation: Orphanet classifies anemia as frequent (79-30%) in primary myelofibrosis.
  - reference: PMID:36332787
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Clinical manifestations of MF include splenomegaly, constitutional symptoms, and anemia, whose pathogenesis is multifactorial and largely due to ineffective erythropoiesis and is clinically associated with poor quality of life and reduced overall survival."
    explanation: Review confirms anemia as a key clinical manifestation with multifactorial pathogenesis.
- category: Constitutional
  name: Fatigue
  frequency: FREQUENT
  description: >-
    Profound fatigue is one of the most debilitating symptoms, significantly
    impacting quality of life.
  phenotype_term:
    preferred_term: Fatigue
    term:
      id: HP:0012378
      label: Fatigue
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0012378 | Fatigue | Frequent (79-30%)"
    explanation: Orphanet classifies fatigue as frequent (79-30%) in primary myelofibrosis.
  - reference: PMID:28808761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Clinical manifestations of MF include cytopenia, fatigue and constitutional symptoms such as low-grade fever, weight loss and night sweats."
    explanation: Review identifies fatigue as a primary clinical manifestation of myelofibrosis.
- category: Constitutional
  name: Cachexia
  frequency: VERY_RARE
  description: >-
    Weight loss and cachexia from hypermetabolic state driven by inflammatory
    cytokine production.
  phenotype_term:
    preferred_term: Cachexia
    term:
      id: HP:0004326
      label: Cachexia
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0004326 | Cachexia | Very rare (<4-1%)"
    explanation: Orphanet classifies cachexia as very rare in primary myelofibrosis.
  - reference: PMID:33197049
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Additional disease features include bone marrow reticulin/collagen fibrosis, aberrant inflammatory cytokine expression, anemia, hepatosplenomegaly, extramedullary hematopoiesis (EMH), constitutional symptoms, cachexia, leukemic progression, and shortened survival."
    explanation: Tefferi 2021 review lists cachexia as a recognized disease feature of PMF.
- category: Hematologic
  name: Thrombocytopenia
  frequency: FREQUENT
  description: >-
    Low platelet count develops as disease progresses, reflecting bone marrow
    failure and splenic sequestration. Increases bleeding risk.
  phenotype_term:
    preferred_term: Thrombocytopenia
    term:
      id: HP:0001873
      label: Thrombocytopenia
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001873 | Thrombocytopenia | Frequent (79-30%)"
    explanation: Orphanet classifies thrombocytopenia as frequent (79-30%) in primary myelofibrosis.
- category: Abdominal
  name: Hepatomegaly
  frequency: FREQUENT
  description: >-
    Liver enlargement from extramedullary hematopoiesis and portal hypertension.
  phenotype_term:
    preferred_term: Hepatomegaly
    term:
      id: HP:0002240
      label: Hepatomegaly
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0002240 | Hepatomegaly | Frequent (79-30%)"
    explanation: Orphanet classifies hepatomegaly as frequent (79-30%) in primary myelofibrosis.
- category: Constitutional
  name: Pallor
  frequency: FREQUENT
  description: >-
    Pallor due to progressive anemia from ineffective erythropoiesis and
    bone marrow failure.
  phenotype_term:
    preferred_term: Pallor
    term:
      id: HP:0000980
      label: Pallor
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0000980 | Pallor | Frequent (79-30%)"
    explanation: Orphanet classifies pallor as frequent (79-30%) in primary myelofibrosis.
- category: Abdominal
  name: Hepatosplenomegaly
  frequency: FREQUENT
  description: >-
    Combined hepatic and splenic enlargement from extramedullary hematopoiesis
    is a characteristic finding, particularly in overt PMF.
  phenotype_term:
    preferred_term: Hepatosplenomegaly
    term:
      id: HP:0001433
      label: Hepatosplenomegaly
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001433 | Hepatosplenomegaly | Frequent (79-30%)"
    explanation: Orphanet classifies hepatosplenomegaly as frequent (79-30%) in primary myelofibrosis.
  - reference: PMID:33197049
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Additional disease features include bone marrow reticulin/collagen fibrosis, aberrant inflammatory cytokine expression, anemia, hepatosplenomegaly, extramedullary hematopoiesis (EMH), constitutional symptoms, cachexia, leukemic progression, and shortened survival."
    explanation: Tefferi 2021 review lists hepatosplenomegaly as a core disease feature.
- category: Hematologic
  name: Abnormal Megakaryocyte Morphology
  frequency: FREQUENT
  diagnostic: true
  description: >-
    Megakaryocyte atypia with clustering, abnormal lobation (cloud-like and
    hyperlobated nuclei), and aberrant maturation is a hallmark diagnostic
    feature of PMF.
  phenotype_term:
    preferred_term: Abnormal megakaryocyte morphology
    term:
      id: HP:0012143
      label: Abnormal megakaryocyte morphology
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0012143 | Abnormal megakaryocyte morphology | Frequent (79-30%)"
    explanation: Orphanet classifies abnormal megakaryocyte morphology as frequent (79-30%) in primary myelofibrosis.
  - reference: PMID:41514563
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Primary myelofibrosis (PMF) is a Philadelphia chromosome (Ph)-negative myeloproliferative neoplasm (MPN) that features clonal proliferation of atypical megakaryocytes and myeloid cells, fibrosis of the bone marrow, extramedullary hematopoiesis, and increased risk of leukemic transformation to acute myeloid leukemia (AML)."
    explanation: Review highlights atypical megakaryocyte proliferation as a defining feature of PMF.
- category: Hematologic
  name: Abnormal Bone Marrow Cell Morphology
  frequency: VERY_FREQUENT
  diagnostic: true
  description: >-
    Characteristic bone marrow morphological changes including reticulin and
    collagen fibrosis, megakaryocyte atypia, and abnormal myeloid maturation
    are the primary diagnostic criteria for PMF.
  phenotype_term:
    preferred_term: Abnormal bone marrow cell morphology
    term:
      id: HP:0005561
      label: Abnormal bone marrow cell morphology
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0005561 | Abnormality of bone marrow cell morphology | Very frequent (99-80%)"
    explanation: Orphanet classifies abnormality of bone marrow cell morphology as very frequent (99-80%) in primary myelofibrosis.
- category: Constitutional
  name: Low-Grade Fever
  frequency: OCCASIONAL
  description: >-
    Low-grade fever is a constitutional symptom driven by aberrant inflammatory
    cytokine expression, particularly IL-6 and TNF-alpha.
  phenotype_term:
    preferred_term: Low-grade fever
    term:
      id: HP:0011134
      label: Low-grade fever
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0011134 | Low-grade fever | Occasional (29-5%)"
    explanation: Orphanet classifies low-grade fever as occasional (29-5%) in primary myelofibrosis.
  - reference: PMID:28808761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Clinical manifestations of MF include cytopenia, fatigue and constitutional symptoms such as low-grade fever, weight loss and night sweats."
    explanation: Review identifies low-grade fever as one of the constitutional symptoms of myelofibrosis.
- category: Constitutional
  name: Fever
  frequency: OCCASIONAL
  description: >-
    Fever occurs as a constitutional symptom in PMF, driven by the inflammatory
    cytokine milieu. Must be distinguished from infection-related fever.
  phenotype_term:
    preferred_term: Fever
    term:
      id: HP:0001945
      label: Fever
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001945 | Fever | Occasional (29-5%)"
    explanation: Orphanet classifies fever as occasional (29-5%) in primary myelofibrosis.
  - reference: PMID:32300883
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Philadelphia-negative myeloproliferative neoplasms (MPNs), essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF), are rare clonal hematopoietic stem cell disorders accompanied by a strong inflammatory milieu, which is directly responsible for constitutional symptoms associated with the disease, such as fever, weight loss or night sweats."
    explanation: Confirms fever as a constitutional symptom directly caused by the inflammatory milieu in MPN including myelofibrosis.
- category: Constitutional
  name: Anorexia
  frequency: OCCASIONAL
  description: >-
    Loss of appetite contributing to weight loss and cachexia, driven by
    inflammatory cytokines and mechanical effects of splenomegaly.
  phenotype_term:
    preferred_term: Anorexia
    term:
      id: HP:0002039
      label: Anorexia
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0002039 | Anorexia | Occasional (29-5%)"
    explanation: Orphanet classifies anorexia as occasional (29-5%) in primary myelofibrosis.
- category: Hematologic
  name: Pancytopenia
  frequency: OCCASIONAL
  description: >-
    Reduction in all blood cell lineages due to progressive marrow failure
    from fibrosis. More common in advanced (overt) PMF.
  phenotype_term:
    preferred_term: Pancytopenia
    term:
      id: HP:0001876
      label: Pancytopenia
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001876 | Pancytopenia | Occasional (29-5%)"
    explanation: Orphanet classifies pancytopenia as occasional (29-5%) in primary myelofibrosis.
- category: Hematologic
  name: Thrombocytosis
  frequency: OCCASIONAL
  description: >-
    Elevated platelet count, particularly in prefibrotic PMF where it may
    mimic essential thrombocythemia. Platelet count declines as disease
    progresses to overt fibrotic phase.
  phenotype_term:
    preferred_term: Thrombocytosis
    term:
      id: HP:0001894
      label: Thrombocytosis
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001894 | Thrombocytosis | Occasional (29-5%)"
    explanation: Orphanet classifies thrombocytosis as occasional (29-5%) in primary myelofibrosis.
- category: Hematologic
  name: Leukocytosis
  frequency: OCCASIONAL
  description: >-
    Elevated white blood cell count, a minor diagnostic criterion for PMF.
    Leukocytosis is an independent risk factor for thrombosis in prefibrotic PMF.
  phenotype_term:
    preferred_term: Leukocytosis
    term:
      id: HP:0001974
      label: Increased total leukocyte count
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001974 | Leukocytosis | Occasional (29-5%)"
    explanation: Orphanet classifies leukocytosis as occasional (29-5%) in primary myelofibrosis.
  - reference: PMID:28808761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Minor criteria, include a) anemia not attributed to a comorbid condition, b) leukocytosis ≥ 11 × 109, c) palpable splenomegaly, d) lactate dehydrogenase (LDH) level above normal limit of institutional reference range and e) leukoerythroblastosis"
    explanation: WHO diagnostic criteria list leukocytosis as a minor criterion for PMF diagnosis.
- category: Hematologic
  name: Extramedullary Hematopoiesis
  frequency: OCCASIONAL
  description: >-
    Hematopoiesis shifts to spleen, liver, and other sites as bone marrow
    function declines. Drives organomegaly and can cause complications at
    unusual sites including pleura, peritoneum, and CNS.
  phenotype_term:
    preferred_term: Extramedullary hematopoiesis
    term:
      id: HP:0001978
      label: Extramedullary hematopoiesis
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001978 | Extramedullary hematopoiesis | Occasional (29-5%)"
    explanation: Orphanet classifies extramedullary hematopoiesis as occasional (29-5%) in primary myelofibrosis.
  - reference: PMID:33197049
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Additional disease features include bone marrow reticulin/collagen fibrosis, aberrant inflammatory cytokine expression, anemia, hepatosplenomegaly, extramedullary hematopoiesis (EMH), constitutional symptoms, cachexia, leukemic progression, and shortened survival."
    explanation: Tefferi 2021 review lists extramedullary hematopoiesis as a core disease feature of PMF.
- category: Hematologic
  name: Poikilocytosis
  frequency: OCCASIONAL
  description: >-
    Abnormal red blood cell shapes including dacrocytes (tear-drop cells)
    are characteristic of the leukoerythroblastic blood picture in PMF.
  phenotype_term:
    preferred_term: Poikilocytosis
    term:
      id: HP:0004447
      label: Poikilocytosis
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0004447 | Poikilocytosis | Occasional (29-5%)"
    explanation: Orphanet classifies poikilocytosis as occasional (29-5%) in primary myelofibrosis.
- category: Hematologic
  name: Abnormal Bleeding
  frequency: OCCASIONAL
  description: >-
    Bleeding complications from thrombocytopenia, platelet functional defects,
    and portal hypertension-related varices. Bleeding events are more common
    in MF than in other MPNs.
  phenotype_term:
    preferred_term: Abnormal bleeding
    term:
      id: HP:0001892
      label: Abnormal bleeding
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001892 | Abnormal bleeding | Occasional (29-5%)"
    explanation: Orphanet classifies abnormal bleeding as occasional (29-5%) in primary myelofibrosis.
  - reference: PMID:28808761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Bleeding and thrombosis are long recognized complications of myelofibrosis (MF) and contribute significantly to its morbidity and mortality."
    explanation: Review confirms bleeding as a recognized complication contributing to MF morbidity and mortality.
- category: Vascular
  name: Arterial Thrombosis
  frequency: OCCASIONAL
  description: >-
    Arterial thrombotic events include stroke, peripheral vascular disease,
    and acute coronary syndrome. Risk is comparable to essential thrombocythemia.
  phenotype_term:
    preferred_term: Arterial thrombosis
    term:
      id: HP:0004420
      label: Arterial thrombosis
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0004420 | Arterial thrombosis | Occasional (29-5%)"
    explanation: Orphanet classifies arterial thrombosis as occasional (29-5%) in primary myelofibrosis.
  - reference: PMID:28808761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Both arterial and venous thrombotic events are not uncommon in patients with PMF"
    explanation: Review confirms arterial thrombosis as a recognized complication of PMF.
- category: Vascular
  name: Venous Thrombosis
  frequency: OCCASIONAL
  description: >-
    Venous thrombotic events including deep vein thrombosis, pulmonary embolism,
    and splanchnic vein thrombosis (portal vein, Budd-Chiari syndrome).
  phenotype_term:
    preferred_term: Venous thrombosis
    term:
      id: HP:0004936
      label: Venous thrombosis
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0004936 | Venous thrombosis | Occasional (29-5%)"
    explanation: Orphanet classifies venous thrombosis as occasional (29-5%) in primary myelofibrosis.
  - reference: PMID:28808761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Both arterial and venous thrombotic events are not uncommon in patients with PMF"
    explanation: Review confirms venous thrombosis as a recognized complication of PMF.
- category: Abdominal
  name: Portal Hypertension
  frequency: OCCASIONAL
  description: >-
    Portal hypertension from splanchnic vein thrombosis, extramedullary
    hematopoiesis in the liver, and increased hepatic blood flow. Can lead
    to variceal bleeding and ascites.
  phenotype_term:
    preferred_term: Portal hypertension
    term:
      id: HP:0001409
      label: Portal hypertension
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0001409 | Portal hypertension | Occasional (29-5%)"
    explanation: Orphanet classifies portal hypertension as occasional (29-5%) in primary myelofibrosis.
  - reference: PMID:25755427
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Portal hypertension is found in up to 7% of patients."
    explanation: Reports portal hypertension frequency of up to 7% in myeloproliferative disease patients.
- category: Dermatologic
  name: Petechiae
  frequency: OCCASIONAL
  description: >-
    Small hemorrhagic spots from thrombocytopenia and platelet dysfunction.
  phenotype_term:
    preferred_term: Petechiae
    term:
      id: HP:0000967
      label: Petechiae
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0000967 | Petechiae | Occasional (29-5%)"
    explanation: Orphanet classifies petechiae as occasional (29-5%) in primary myelofibrosis.
- category: Dermatologic
  name: Purpura
  frequency: OCCASIONAL
  description: >-
    Purpuric skin lesions from thrombocytopenia and platelet dysfunction.
  phenotype_term:
    preferred_term: Purpura
    term:
      id: HP:0000979
      label: Purpura
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0000979 | Purpura | Occasional (29-5%)"
    explanation: Orphanet classifies purpura as occasional (29-5%) in primary myelofibrosis.
- category: Dermatologic
  name: Ecchymosis
  frequency: OCCASIONAL
  description: >-
    Easy bruising from thrombocytopenia and coagulopathy.
  phenotype_term:
    preferred_term: Ecchymosis
    term:
      id: HP:0031364
      label: Ecchymosis
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0031364 | Ecchymosis | Occasional (29-5%)"
    explanation: Orphanet classifies ecchymosis as occasional (29-5%) in primary myelofibrosis.
- category: Abdominal
  name: Flank Pain
  frequency: OCCASIONAL
  description: >-
    Flank pain from massive splenomegaly or splenic infarction.
  phenotype_term:
    preferred_term: Flank pain
    term:
      id: HP:0030157
      label: Flank pain
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0030157 | Flank pain | Occasional (29-5%)"
    explanation: Orphanet classifies flank pain as occasional (29-5%) in primary myelofibrosis.
- category: Other
  name: Lymphadenopathy
  frequency: OCCASIONAL
  description: >-
    Lymph node enlargement may occur due to extramedullary hematopoiesis
    at lymph node sites.
  phenotype_term:
    preferred_term: Lymphadenopathy
    term:
      id: HP:0002716
      label: Lymphadenopathy
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0002716 | Lymphadenopathy | Occasional (29-5%)"
    explanation: Orphanet classifies lymphadenopathy as occasional (29-5%) in primary myelofibrosis.
- category: Hematologic
  name: Increased Circulating Lactate Dehydrogenase Concentration
  frequency: VERY_RARE
  diagnostic: true
  notes: >-
    Orphanet classifies LDH elevation as very rare, but it is a WHO minor
    diagnostic criterion for PMF. The Orphanet frequency likely reflects
    population-level reporting rather than clinical prevalence among
    diagnosed patients, where LDH elevation is common.
  description: >-
    Elevated LDH reflecting increased cell turnover and extramedullary
    hematopoiesis. A WHO minor diagnostic criterion for PMF that correlates
    with disease activity.
  phenotype_term:
    preferred_term: Increased circulating lactate dehydrogenase concentration
    term:
      id: HP:0025435
      label: Increased circulating lactate dehydrogenase concentration
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0025435 | Increased circulating lactate dehydrogenase concentration | Very rare (<4-1%)"
    explanation: Orphanet classifies increased LDH as very rare in primary myelofibrosis.
  - reference: PMID:28808761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Minor criteria, include a) anemia not attributed to a comorbid condition, b) leukocytosis ≥ 11 × 109, c) palpable splenomegaly, d) lactate dehydrogenase (LDH) level above normal limit of institutional reference range and e) leukoerythroblastosis"
    explanation: LDH above normal is a WHO minor diagnostic criterion for PMF.
- category: Hematologic
  name: Bone Marrow Hypercellularity
  frequency: OCCASIONAL
  description: >-
    Increased age-adjusted bone marrow cellularity, particularly in the
    prefibrotic phase, with granulocytic proliferation and megakaryocyte
    atypia.
  phenotype_term:
    preferred_term: Bone marrow hypercellularity
    term:
      id: HP:0031020
      label: Bone marrow hypercellularity
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "HP:0031020 | Bone marrow hypercellularity | Occasional (29-5%)"
    explanation: Orphanet classifies bone marrow hypercellularity as occasional (29-5%) in primary myelofibrosis.
  - reference: PMID:28808761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "megakaryocytic proliferation and atypia, without reticulin fibrosis > grade 1, accompanied by increased age-adjusted bone marrow (BM) cellularity, granulocytic proliferation, and often decreased erythropoiesis"
    explanation: WHO diagnostic criteria for prefibrotic PMF include increased age-adjusted bone marrow cellularity.
biochemical:
- name: Lactate Dehydrogenase (LDH)
  notes: >-
    LDH is elevated reflecting increased cell turnover and extramedullary
    hematopoiesis. Levels correlate with disease activity.
- name: Peripheral Blood Smear
  notes: >-
    Leukoerythroblastic picture with tear-drop cells (dacrocytes), nucleated
    red blood cells, and immature granulocytes is characteristic of PMF.
genetic:
- name: JAK2
  association: Somatic Activating Mutations
  notes: >-
    JAK2 V617F occurs in approximately 60% of PMF patients. Provides rationale
    for JAK inhibitor therapy.
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "JAK2 | Janus kinase 2 | hgnc:6192 | Disease-causing somatic mutation(s) in"
    explanation: Orphanet confirms JAK2 as harboring disease-causing somatic mutations in PMF.
- name: CALR
  association: Somatic Frameshift Mutations
  notes: >-
    CALR exon 9 frameshift mutations occur in approximately 25% of PMF, mostly
    type 1 (52bp deletion) or type 2 (5bp insertion). Generally associated
    with better prognosis than JAK2 mutations.
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "CALR | calreticulin | hgnc:1455 | Disease-causing somatic mutation(s) in"
    explanation: Orphanet confirms CALR as harboring disease-causing somatic mutations in PMF.
- name: MPL
  association: Somatic Activating Mutations
  notes: >-
    MPL W515L/K mutations occur in approximately 5% of PMF. Activates JAK-STAT
    signaling through the thrombopoietin receptor.
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "MPL | MPL proto-oncogene, thrombopoietin receptor | hgnc:7217 | Disease-causing somatic mutation(s) in"
    explanation: Orphanet confirms MPL as harboring disease-causing somatic mutations in PMF.
- name: TET2
  association: Somatic Loss-of-Function Mutations
  notes: >-
    TET2 mutations are found in a subset of PMF patients and contribute to
    epigenetic dysregulation. TET2 encodes a methylcytosine dioxygenase
    involved in DNA demethylation.
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "TET2 | tet methylcytosine dioxygenase 2 | hgnc:25941 | Disease-causing somatic mutation(s) in"
    explanation: Orphanet lists TET2 as harboring disease-causing somatic mutations in primary myelofibrosis.
- name: ASXL1
  association: Somatic Loss-of-Function Mutations
  notes: >-
    ASXL1 mutations are adverse prognostic markers independent of driver
    mutation status. Part of high molecular risk (HMR) category.
  evidence:
  - reference: PMID:33197049
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "SRSF2, ASXL1, and U2AF1-Q157 mutations predict inferior survival in PMF, independent of each other and other risk factors."
    explanation: Tefferi 2021 review confirms ASXL1 as an adverse prognostic mutation in PMF.
- name: EZH2
  association: Somatic Loss-of-Function Mutations
  notes: >-
    EZH2 mutations contribute to epigenetic dysregulation in PMF.
    EZH2 encodes a histone methyltransferase in the polycomb repressive
    complex 2 (PRC2).
- name: SRSF2
  association: Somatic Mutations
  notes: >-
    SRSF2 mutations predict inferior survival in PMF, independent of
    driver mutation status and other risk factors. Part of high molecular
    risk (HMR) category. SRSF2 encodes a serine/arginine-rich splicing factor.
  evidence:
  - reference: PMID:33197049
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "SRSF2, ASXL1, and U2AF1-Q157 mutations predict inferior survival in PMF, independent of each other and other risk factors."
    explanation: Tefferi 2021 review identifies SRSF2 as an adverse prognostic mutation in PMF.
- name: U2AF1
  association: Somatic Mutations
  notes: >-
    U2AF1 Q157 mutations predict inferior survival in PMF, independent of
    driver mutation status. U2AF1 encodes a small subunit of the U2
    auxiliary splicing factor.
  evidence:
  - reference: PMID:33197049
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "SRSF2, ASXL1, and U2AF1-Q157 mutations predict inferior survival in PMF, independent of each other and other risk factors."
    explanation: Tefferi 2021 review identifies U2AF1-Q157 as an adverse prognostic mutation in PMF.
treatments:
- name: Ruxolitinib
  description: >-
    JAK1/JAK2 inhibitor approved for intermediate-2 and high-risk PMF. Provides
    marked reduction in spleen size and constitutional symptoms but does not
    significantly alter disease course or prevent leukemic transformation.
  treatment_term:
    preferred_term: targeted therapy
    term:
      id: NCIT:C93352
      label: Targeted Therapy
    therapeutic_agent:
    - preferred_term: ruxolitinib
      term:
        id: CHEBI:66919
        label: ruxolitinib
- name: Fedratinib
  description: >-
    JAK2 inhibitor approved for intermediate-2 and high-risk PMF, including
    patients previously treated with ruxolitinib. Selective JAK2 inhibition
    with similar efficacy profile.
  treatment_term:
    preferred_term: targeted therapy
    term:
      id: NCIT:C93352
      label: Targeted Therapy
    therapeutic_agent:
    - preferred_term: fedratinib
      term:
        id: NCIT:C88293
        label: Fedratinib
- name: Allogeneic Stem Cell Transplantation
  description: >-
    Only potentially curative treatment for PMF. Considered for younger patients
    with high-risk disease. Significant transplant-related morbidity and mortality
    must be weighed against disease risk.
  treatment_term:
    preferred_term: hematopoietic stem cell transplantation
    term:
      id: MAXO:0000747
      label: hematopoietic stem cell transplantation
- name: Hydroxyurea
  description: >-
    Cytoreductive therapy for symptomatic splenomegaly or thrombocytosis.
    Provides modest benefit but does not address constitutional symptoms
    as effectively as JAK inhibitors.
  treatment_term:
    preferred_term: chemotherapy
    term:
      id: MAXO:0000646
      label: cancer chemotherapy
    therapeutic_agent:
    - preferred_term: hydroxyurea
      term:
        id: CHEBI:44423
        label: hydroxyurea
- name: Anagrelide
  description: >-
    Platelet-lowering agent used for thrombocytosis when present. Selective
    megakaryocyte inhibitor.
  treatment_term:
    preferred_term: targeted therapy
    term:
      id: NCIT:C93352
      label: Targeted Therapy
    therapeutic_agent:
    - preferred_term: anagrelide
      term:
        id: CHEBI:142290
        label: anagrelide
- name: Momelotinib
  description: >-
    JAK1/JAK2 and ACVR1/ALK2 inhibitor FDA-approved in 2023 for intermediate-
    or high-risk PMF with anemia. Uniquely addresses anemia by suppressing
    hepcidin through ACVR1 inhibition. Demonstrated durable symptom, spleen,
    and anemia benefits in the MOMENTUM trial.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
    therapeutic_agent:
    - preferred_term: momelotinib
      term:
        id: CHEBI:91407
        label: momelotinib
  evidence:
  - reference: PMID:37517413
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Momelotinib was associated with durable symptom, spleen, and anaemia benefits, late responses after week 24, and favourable safety through week 48."
    explanation: MOMENTUM phase 3 trial demonstrates durable efficacy of momelotinib for symptom, spleen, and anemia endpoints in previously JAK inhibitor-treated MF patients.
- name: Pacritinib
  description: >-
    Selective JAK2/IRAK1/ACVR1 inhibitor, JAK1-sparing, FDA-approved in 2022
    for PMF with severe thrombocytopenia (platelets less than 50 x 10^9/L).
    Can be administered at full dose regardless of baseline platelet count.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
    therapeutic_agent:
    - preferred_term: pacritinib
      term:
        id: CHEBI:231350
        label: pacritinib
  evidence:
  - reference: PMID:35622972
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "the dose finding PAC203 study endorsed the safety and efficacy of 200 mg twice daily, leading to the approval of PAC for the treatment of patients with MF with platelets ≤ 50 × 109/L."
    explanation: Review of pacritinib development describes its approval for thrombocytopenic MF.
epidemiology:
- name: European Annual Incidence
  description: >-
    Annual incidence of primary myelofibrosis in Europe estimated at
    1-9 per 100,000.
  unit: cases per 100,000
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "1-9 / 100 000 | Europe | Annual incidence | EXPERT"
    explanation: Orphanet reports European annual incidence of 1-9 per 100,000 based on expert opinion.
- name: European Point Prevalence
  description: >-
    Point prevalence of primary myelofibrosis in Europe estimated at
    1-9 per 100,000.
  unit: cases per 100,000
  evidence:
  - reference: ORPHA:824
    supports: SUPPORT
    snippet: "1-9 / 100 000 | Europe | Point prevalence | INST"
    explanation: Orphanet reports European point prevalence of 1-9 per 100,000 based on institutional data.
disease_term:
  preferred_term: primary myelofibrosis
  term:
    id: MONDO:0009692
    label: primary myelofibrosis

classifications:
  icdo_morphology:
    classification_value: Leukemia
  harrisons_chapter:
  - classification_value: cancer
  - classification_value: hematologic malignancy
references:
- reference: DOI:10.1007/s00277-025-06191-7
  title: How I diagnose and treat patients in the pre-fibrotic phase of primary myelofibrosis (pre-PMF) - practical approaches of a German expert panel discussion in 2024
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: How I diagnose and treat patients in the pre-fibrotic phase of primary myelofibrosis (pre-PMF) - practical approaches of a German expert panel discussion in 2024
    supporting_text: The prefibrotic phase of primary myelofibrosis (pre-PMF) represents a distinct subentity within the spectrum of myeloproliferative neoplasms (MPNs), recognized by the World Health Organization (WHO) and the International Consensus Classification (ICC).
    evidence:
    - reference: DOI:10.1007/s00277-025-06191-7
      reference_title: How I diagnose and treat patients in the pre-fibrotic phase of primary myelofibrosis (pre-PMF) - practical approaches of a German expert panel discussion in 2024
      supports: SUPPORT
      evidence_source: OTHER
      snippet: The prefibrotic phase of primary myelofibrosis (pre-PMF) represents a distinct subentity within the spectrum of myeloproliferative neoplasms (MPNs), recognized by the World Health Organization (WHO) and the International Consensus Classification (ICC).
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.1007/s00428-022-03480-8
  title: 'International Consensus Classification of myeloid and lymphoid neoplasms: myeloproliferative neoplasms'
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: 'International Consensus Classification of myeloid and lymphoid neoplasms: myeloproliferative neoplasms'
    supporting_text: The recently published International Consensus Classification (ICC) of myeloid neoplasms summarized the results of an in-depth effort by pathologists, oncologists, and geneticists aimed to update the 2017 World Health Organization classification system for hematopoietic tumors.
    evidence:
    - reference: DOI:10.1007/s00428-022-03480-8
      reference_title: 'International Consensus Classification of myeloid and lymphoid neoplasms: myeloproliferative neoplasms'
      supports: SUPPORT
      evidence_source: OTHER
      snippet: The recently published International Consensus Classification (ICC) of myeloid neoplasms summarized the results of an in-depth effort by pathologists, oncologists, and geneticists aimed to update the 2017 World Health Organization classification system for hematopoietic tumors.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.1007/s10238-025-01830-9
  title: 'From symptom scales to regulatory endpoints: the evolution and clinical impact of patient-reported outcome measures in myeloproliferative neoplasms'
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: Myeloproliferative neoplasms (MPNs) are symptom-driven hematologic malignancies characterized by persistent and heterogeneous symptom burden that significantly impairs health-related quality of life (HRQoL).
    supporting_text: Myeloproliferative neoplasms (MPNs) are symptom-driven hematologic malignancies characterized by persistent and heterogeneous symptom burden that significantly impairs health-related quality of life (HRQoL).
    evidence:
    - reference: DOI:10.1007/s10238-025-01830-9
      reference_title: 'From symptom scales to regulatory endpoints: the evolution and clinical impact of patient-reported outcome measures in myeloproliferative neoplasms'
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Myeloproliferative neoplasms (MPNs) are symptom-driven hematologic malignancies characterized by persistent and heterogeneous symptom burden that significantly impairs health-related quality of life (HRQoL).
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.1007/s11899-024-00739-6
  title: Prognostic and Predictive Models in Myelofibrosis
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: of Review Myelofibrosis (MF) includes prefibrotic primary MF (pre-PMF), overt-PMF and secondary MF (SMF).
    supporting_text: of Review Myelofibrosis (MF) includes prefibrotic primary MF (pre-PMF), overt-PMF and secondary MF (SMF).
    evidence:
    - reference: DOI:10.1007/s11899-024-00739-6
      reference_title: Prognostic and Predictive Models in Myelofibrosis
      supports: SUPPORT
      evidence_source: OTHER
      snippet: of Review Myelofibrosis (MF) includes prefibrotic primary MF (pre-PMF), overt-PMF and secondary MF (SMF).
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.1007/s12325-024-02928-4
  title: 'Momelotinib versus Continued Ruxolitinib or Best Available Therapy in JAK Inhibitor-Experienced Patients with Myelofibrosis and Anemia: Subgroup Analysis of SIMPLIFY-2'
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: Some Janus kinase (JAK) inhibitors such as ruxolitinib and fedratinib do not address and may worsen anemia in patients with myelofibrosis.
    supporting_text: Some Janus kinase (JAK) inhibitors such as ruxolitinib and fedratinib do not address and may worsen anemia in patients with myelofibrosis.
    evidence:
    - reference: DOI:10.1007/s12325-024-02928-4
      reference_title: 'Momelotinib versus Continued Ruxolitinib or Best Available Therapy in JAK Inhibitor-Experienced Patients with Myelofibrosis and Anemia: Subgroup Analysis of SIMPLIFY-2'
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Some Janus kinase (JAK) inhibitors such as ruxolitinib and fedratinib do not address and may worsen anemia in patients with myelofibrosis.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.1038/s41408-023-00878-8
  title: 'Blast phase myeloproliferative neoplasm: contemporary review and 2024 treatment algorithm'
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: 'Blast phase myeloproliferative neoplasm: contemporary review and 2024 treatment algorithm'
    supporting_text: Leukemic transformation in myeloproliferative neoplasms (MPN), also referred to as “blast-phase MPN”, is the most feared disease complication, with incidence estimates of 1–4% for essential thrombocythemia, 3–7% for polycythemia vera, and 9–13% for primary myelofibrosis.
    evidence:
    - reference: DOI:10.1038/s41408-023-00878-8
      reference_title: 'Blast phase myeloproliferative neoplasm: contemporary review and 2024 treatment algorithm'
      supports: SUPPORT
      evidence_source: OTHER
      snippet: Leukemic transformation in myeloproliferative neoplasms (MPN), also referred to as “blast-phase MPN”, is the most feared disease complication, with incidence estimates of 1–4% for essential thrombocythemia, 3–7% for polycythemia vera, and 9–13% for primary myelofibrosis.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.1038/s41408-024-01029-3
  title: 'Momelotinib for myelofibrosis: our 14 years of experience with 100 clinical trial patients and recent FDA approval'
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: 'Momelotinib for myelofibrosis: our 14 years of experience with 100 clinical trial patients and recent FDA approval'
    supporting_text: 'Momelotinib for myelofibrosis: our 14 years of experience with 100 clinical trial patients and recent FDA approval'
- reference: DOI:10.1093/oncolo/oyab058
  title: Treatment Patterns, Health Care Resource Utilization, and Cost in Patients with Myelofibrosis in the United States
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: This study analyses treatment patterns, health care resource utilization (HCRU), and costs in patients with myelofibrosis (MF) and a subgroup treated with ruxolitinib (RUX).
    supporting_text: This study analyses treatment patterns, health care resource utilization (HCRU), and costs in patients with myelofibrosis (MF) and a subgroup treated with ruxolitinib (RUX).
    evidence:
    - reference: DOI:10.1093/oncolo/oyab058
      reference_title: Treatment Patterns, Health Care Resource Utilization, and Cost in Patients with Myelofibrosis in the United States
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: This study analyses treatment patterns, health care resource utilization (HCRU), and costs in patients with myelofibrosis (MF) and a subgroup treated with ruxolitinib (RUX).
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.1111/bjh.19164
  title: 'Diagnosis and evaluation of prognosis of myelofibrosis: A British Society for Haematology Guideline'
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: 'Diagnosis and evaluation of prognosis of myelofibrosis: A British Society for Haematology Guideline'
    supporting_text: 'Diagnosis and evaluation of prognosis of myelofibrosis: A British Society for Haematology Guideline'
- reference: DOI:10.1182/blood-2024-210274
  title: Real-Word Effectiveness of Pacritinib in Patients with Myelofibrosis Who Have Thrombocytopenia and Anemia
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: The co-occurrence of thrombocytopenia and anemia (bicytopenia) in patients with myelofibrosis (MF) is a therapeutic challenge because of treatment-related myelosuppression from JAK1/2 inhibitors.
    supporting_text: The co-occurrence of thrombocytopenia and anemia (bicytopenia) in patients with myelofibrosis (MF) is a therapeutic challenge because of treatment-related myelosuppression from JAK1/2 inhibitors.
    evidence:
    - reference: DOI:10.1182/blood-2024-210274
      reference_title: Real-Word Effectiveness of Pacritinib in Patients with Myelofibrosis Who Have Thrombocytopenia and Anemia
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: The co-occurrence of thrombocytopenia and anemia (bicytopenia) in patients with myelofibrosis (MF) is a therapeutic challenge because of treatment-related myelosuppression from JAK1/2 inhibitors.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.1182/hematology.2022000340
  title: New approaches to tackle cytopenic myelofibrosis
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: Myelofibrosis (MF) is a clonal hematopoietic stem cell neoplasm characterized by constitutional symptoms, splenomegaly, and risks of marrow failure or leukemic transformation and is universally driven by Jak/STAT pathway activation.
    supporting_text: Myelofibrosis (MF) is a clonal hematopoietic stem cell neoplasm characterized by constitutional symptoms, splenomegaly, and risks of marrow failure or leukemic transformation and is universally driven by Jak/STAT pathway activation.
    evidence:
    - reference: DOI:10.1182/hematology.2022000340
      reference_title: New approaches to tackle cytopenic myelofibrosis
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Myelofibrosis (MF) is a clonal hematopoietic stem cell neoplasm characterized by constitutional symptoms, splenomegaly, and risks of marrow failure or leukemic transformation and is universally driven by Jak/STAT pathway activation.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.1186/s13045-024-01571-4
  title: 'A practical approach on the classifications of myeloid neoplasms and acute leukemia: WHO and ICC'
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: 'In 2022, two new classifications of myeloid neoplasms and acute leukemias were published: the 5th edition WHO Classification (WHO-HAEM5) and the International Consensus Classification (ICC).'
    supporting_text: 'In 2022, two new classifications of myeloid neoplasms and acute leukemias were published: the 5th edition WHO Classification (WHO-HAEM5) and the International Consensus Classification (ICC).'
    evidence:
    - reference: DOI:10.1186/s13045-024-01571-4
      reference_title: 'A practical approach on the classifications of myeloid neoplasms and acute leukemia: WHO and ICC'
      supports: SUPPORT
      evidence_source: OTHER
      snippet: 'In 2022, two new classifications of myeloid neoplasms and acute leukemias were published: the 5th edition WHO Classification (WHO-HAEM5) and the International Consensus Classification (ICC).'
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.3389/fonc.2024.1411972
  title: Momelotinib – a promising advancement in the management of myelofibrosis in adults with anemia
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: Myelofibrosis (MF) is a rare BCR-ABL negative myeloproliferative neoplasm characterized by clonal proliferation of stem cells, with mutations in JAK2, CALR, or MPL genes.
    supporting_text: Myelofibrosis (MF) is a rare BCR-ABL negative myeloproliferative neoplasm characterized by clonal proliferation of stem cells, with mutations in JAK2, CALR, or MPL genes.
    evidence:
    - reference: DOI:10.3389/fonc.2024.1411972
      reference_title: Momelotinib – a promising advancement in the management of myelofibrosis in adults with anemia
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Myelofibrosis (MF) is a rare BCR-ABL negative myeloproliferative neoplasm characterized by clonal proliferation of stem cells, with mutations in JAK2, CALR, or MPL genes.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.3390/cancers15133331
  title: Association of Myelofibrosis Phenotypes with Clinical Manifestations, Molecular Profiles, and Treatments
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: Myelofibrosis (MF) presents an array of clinical manifestations and molecular profiles.
    supporting_text: Myelofibrosis (MF) presents an array of clinical manifestations and molecular profiles.
    evidence:
    - reference: DOI:10.3390/cancers15133331
      reference_title: Association of Myelofibrosis Phenotypes with Clinical Manifestations, Molecular Profiles, and Treatments
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Myelofibrosis (MF) presents an array of clinical manifestations and molecular profiles.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.3390/cancers15205027
  title: A Prognostic Model to Predict Ruxolitinib Discontinuation and Death in Patients with Myelofibrosis
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: Most patients with myelofibrosis (MF) discontinue ruxolitinib (JAK1/JAK2 inhibitor) in the first 5 years of therapy due to therapy failure.
    supporting_text: Most patients with myelofibrosis (MF) discontinue ruxolitinib (JAK1/JAK2 inhibitor) in the first 5 years of therapy due to therapy failure.
    evidence:
    - reference: DOI:10.3390/cancers15205027
      reference_title: A Prognostic Model to Predict Ruxolitinib Discontinuation and Death in Patients with Myelofibrosis
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Most patients with myelofibrosis (MF) discontinue ruxolitinib (JAK1/JAK2 inhibitor) in the first 5 years of therapy due to therapy failure.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.3390/cancers16071416
  title: Real-World Electronic Medical Records Data Identify Risk Factors for Myelofibrosis and Can Be Used to Validate Established Prognostic Scores
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: Myelofibrosis (MF) is a myeloproliferative neoplasia arising de novo as primary myelofibrosis (PMF) or secondary to polycythemia vera or essential thrombocythemia.
    supporting_text: Myelofibrosis (MF) is a myeloproliferative neoplasia arising de novo as primary myelofibrosis (PMF) or secondary to polycythemia vera or essential thrombocythemia.
    evidence:
    - reference: DOI:10.3390/cancers16071416
      reference_title: Real-World Electronic Medical Records Data Identify Risk Factors for Myelofibrosis and Can Be Used to Validate Established Prognostic Scores
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Myelofibrosis (MF) is a myeloproliferative neoplasia arising de novo as primary myelofibrosis (PMF) or secondary to polycythemia vera or essential thrombocythemia.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.3390/cancers16234114
  title: Biological Markers of Myeloproliferative Neoplasms in Children, Adolescents and Young Adults
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: Myeloproliferative neoplasms (MPNs) are clonal hematopoietic cancers characterized by hyperproliferation of the myeloid lineages.
    supporting_text: Myeloproliferative neoplasms (MPNs) are clonal hematopoietic cancers characterized by hyperproliferation of the myeloid lineages.
    evidence:
    - reference: DOI:10.3390/cancers16234114
      reference_title: Biological Markers of Myeloproliferative Neoplasms in Children, Adolescents and Young Adults
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Myeloproliferative neoplasms (MPNs) are clonal hematopoietic cancers characterized by hyperproliferation of the myeloid lineages.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.3390/cancers17111834
  title: Current Advances in the Diagnosis and Treatment of Major Myeloproliferative Neoplasms
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: Myeloproliferative neoplasms (MPNs) are a group of rare blood cancers characterized by the excessive production of blood cells in the bone marrow.
    supporting_text: Myeloproliferative neoplasms (MPNs) are a group of rare blood cancers characterized by the excessive production of blood cells in the bone marrow.
    evidence:
    - reference: DOI:10.3390/cancers17111834
      reference_title: Current Advances in the Diagnosis and Treatment of Major Myeloproliferative Neoplasms
      supports: SUPPORT
      evidence_source: OTHER
      snippet: Myeloproliferative neoplasms (MPNs) are a group of rare blood cancers characterized by the excessive production of blood cells in the bone marrow.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.3390/curroncol32060339
  title: 'Myelofibrosis: Treatment Options After Ruxolitinib Failure'
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: 'Myelofibrosis: Treatment Options After Ruxolitinib Failure'
    supporting_text: While allogeneic hematopoietic stem cell transplantation remains the only curative therapy for patients with myelofibrosis, its applicability is limited both by the high morbidity and mortality associated with the procedure and by the fact that only a minority of patients are eligible due to age or comorbidities.
    evidence:
    - reference: DOI:10.3390/curroncol32060339
      reference_title: 'Myelofibrosis: Treatment Options After Ruxolitinib Failure'
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: While allogeneic hematopoietic stem cell transplantation remains the only curative therapy for patients with myelofibrosis, its applicability is limited both by the high morbidity and mortality associated with the procedure and by the fact that only a minority of patients are eligible due to age or comorbidities.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
- reference: DOI:10.3390/hematolrep16040067
  title: 'Treatment Strategies Used in Treating Myelofibrosis: State of the Art'
  found_in:
  - Primary_Myelofibrosis-deep-research-falcon.md
  findings:
  - statement: Current drug therapy for myelofibrosis does not alter the natural course of the disease or prolong survival, and allogeneic stem cell transplantation is the only curative treatment modality.
    supporting_text: Current drug therapy for myelofibrosis does not alter the natural course of the disease or prolong survival, and allogeneic stem cell transplantation is the only curative treatment modality.
    evidence:
    - reference: DOI:10.3390/hematolrep16040067
      reference_title: 'Treatment Strategies Used in Treating Myelofibrosis: State of the Art'
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: Current drug therapy for myelofibrosis does not alter the natural course of the disease or prolong survival, and allogeneic stem cell transplantation is the only curative treatment modality.
      explanation: Deep research cited this publication as relevant literature for Primary Myelofibrosis.
📚

References & Deep Research

References

20
How I diagnose and treat patients in the pre-fibrotic phase of primary myelofibrosis (pre-PMF) - practical approaches of a German expert panel discussion in 2024
1 finding
How I diagnose and treat patients in the pre-fibrotic phase of primary myelofibrosis (pre-PMF) - practical approaches of a German expert panel discussion in 2024
"The prefibrotic phase of primary myelofibrosis (pre-PMF) represents a distinct subentity within the spectrum of myeloproliferative neoplasms (MPNs), recognized by the World Health Organization (WHO) and the International Consensus Classification (ICC)."
Show evidence (1 reference)
"The prefibrotic phase of primary myelofibrosis (pre-PMF) represents a distinct subentity within the spectrum of myeloproliferative neoplasms (MPNs), recognized by the World Health Organization (WHO) and the International Consensus Classification (ICC)."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
International Consensus Classification of myeloid and lymphoid neoplasms: myeloproliferative neoplasms
1 finding
International Consensus Classification of myeloid and lymphoid neoplasms: myeloproliferative neoplasms
"The recently published International Consensus Classification (ICC) of myeloid neoplasms summarized the results of an in-depth effort by pathologists, oncologists, and geneticists aimed to update the 2017 World Health Organization classification system for hematopoietic tumors."
Show evidence (1 reference)
"The recently published International Consensus Classification (ICC) of myeloid neoplasms summarized the results of an in-depth effort by pathologists, oncologists, and geneticists aimed to update the 2017 World Health Organization classification system for hematopoietic tumors."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
From symptom scales to regulatory endpoints: the evolution and clinical impact of patient-reported outcome measures in myeloproliferative neoplasms
1 finding
Myeloproliferative neoplasms (MPNs) are symptom-driven hematologic malignancies characterized by persistent and heterogeneous symptom burden that significantly impairs health-related quality of life (HRQoL).
"Myeloproliferative neoplasms (MPNs) are symptom-driven hematologic malignancies characterized by persistent and heterogeneous symptom burden that significantly impairs health-related quality of life (HRQoL)."
Show evidence (1 reference)
DOI:10.1007/s10238-025-01830-9 SUPPORT Human Clinical
"Myeloproliferative neoplasms (MPNs) are symptom-driven hematologic malignancies characterized by persistent and heterogeneous symptom burden that significantly impairs health-related quality of life (HRQoL)."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Prognostic and Predictive Models in Myelofibrosis
1 finding
of Review Myelofibrosis (MF) includes prefibrotic primary MF (pre-PMF), overt-PMF and secondary MF (SMF).
"of Review Myelofibrosis (MF) includes prefibrotic primary MF (pre-PMF), overt-PMF and secondary MF (SMF)."
Show evidence (1 reference)
"of Review Myelofibrosis (MF) includes prefibrotic primary MF (pre-PMF), overt-PMF and secondary MF (SMF)."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Momelotinib versus Continued Ruxolitinib or Best Available Therapy in JAK Inhibitor-Experienced Patients with Myelofibrosis and Anemia: Subgroup Analysis of SIMPLIFY-2
1 finding
Some Janus kinase (JAK) inhibitors such as ruxolitinib and fedratinib do not address and may worsen anemia in patients with myelofibrosis.
"Some Janus kinase (JAK) inhibitors such as ruxolitinib and fedratinib do not address and may worsen anemia in patients with myelofibrosis."
Show evidence (1 reference)
DOI:10.1007/s12325-024-02928-4 SUPPORT Human Clinical
"Some Janus kinase (JAK) inhibitors such as ruxolitinib and fedratinib do not address and may worsen anemia in patients with myelofibrosis."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Blast phase myeloproliferative neoplasm: contemporary review and 2024 treatment algorithm
1 finding
Blast phase myeloproliferative neoplasm: contemporary review and 2024 treatment algorithm
"Leukemic transformation in myeloproliferative neoplasms (MPN), also referred to as “blast-phase MPN”, is the most feared disease complication, with incidence estimates of 1–4% for essential thrombocythemia, 3–7% for polycythemia vera, and 9–13% for primary myelofibrosis."
Show evidence (1 reference)
"Leukemic transformation in myeloproliferative neoplasms (MPN), also referred to as “blast-phase MPN”, is the most feared disease complication, with incidence estimates of 1–4% for essential thrombocythemia, 3–7% for polycythemia vera, and 9–13% for primary myelofibrosis."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Momelotinib for myelofibrosis: our 14 years of experience with 100 clinical trial patients and recent FDA approval
1 finding
Momelotinib for myelofibrosis: our 14 years of experience with 100 clinical trial patients and recent FDA approval
"Momelotinib for myelofibrosis: our 14 years of experience with 100 clinical trial patients and recent FDA approval"
Treatment Patterns, Health Care Resource Utilization, and Cost in Patients with Myelofibrosis in the United States
1 finding
This study analyses treatment patterns, health care resource utilization (HCRU), and costs in patients with myelofibrosis (MF) and a subgroup treated with ruxolitinib (RUX).
"This study analyses treatment patterns, health care resource utilization (HCRU), and costs in patients with myelofibrosis (MF) and a subgroup treated with ruxolitinib (RUX)."
Show evidence (1 reference)
DOI:10.1093/oncolo/oyab058 SUPPORT Human Clinical
"This study analyses treatment patterns, health care resource utilization (HCRU), and costs in patients with myelofibrosis (MF) and a subgroup treated with ruxolitinib (RUX)."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Diagnosis and evaluation of prognosis of myelofibrosis: A British Society for Haematology Guideline
1 finding
Diagnosis and evaluation of prognosis of myelofibrosis: A British Society for Haematology Guideline
"Diagnosis and evaluation of prognosis of myelofibrosis: A British Society for Haematology Guideline"
Real-Word Effectiveness of Pacritinib in Patients with Myelofibrosis Who Have Thrombocytopenia and Anemia
1 finding
The co-occurrence of thrombocytopenia and anemia (bicytopenia) in patients with myelofibrosis (MF) is a therapeutic challenge because of treatment-related myelosuppression from JAK1/2 inhibitors.
"The co-occurrence of thrombocytopenia and anemia (bicytopenia) in patients with myelofibrosis (MF) is a therapeutic challenge because of treatment-related myelosuppression from JAK1/2 inhibitors."
Show evidence (1 reference)
DOI:10.1182/blood-2024-210274 SUPPORT Human Clinical
"The co-occurrence of thrombocytopenia and anemia (bicytopenia) in patients with myelofibrosis (MF) is a therapeutic challenge because of treatment-related myelosuppression from JAK1/2 inhibitors."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
New approaches to tackle cytopenic myelofibrosis
1 finding
Myelofibrosis (MF) is a clonal hematopoietic stem cell neoplasm characterized by constitutional symptoms, splenomegaly, and risks of marrow failure or leukemic transformation and is universally driven by Jak/STAT pathway activation.
"Myelofibrosis (MF) is a clonal hematopoietic stem cell neoplasm characterized by constitutional symptoms, splenomegaly, and risks of marrow failure or leukemic transformation and is universally driven by Jak/STAT pathway activation."
Show evidence (1 reference)
DOI:10.1182/hematology.2022000340 SUPPORT Human Clinical
"Myelofibrosis (MF) is a clonal hematopoietic stem cell neoplasm characterized by constitutional symptoms, splenomegaly, and risks of marrow failure or leukemic transformation and is universally driven by Jak/STAT pathway activation."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
A practical approach on the classifications of myeloid neoplasms and acute leukemia: WHO and ICC
1 finding
In 2022, two new classifications of myeloid neoplasms and acute leukemias were published: the 5th edition WHO Classification (WHO-HAEM5) and the International Consensus Classification (ICC).
"In 2022, two new classifications of myeloid neoplasms and acute leukemias were published: the 5th edition WHO Classification (WHO-HAEM5) and the International Consensus Classification (ICC)."
Show evidence (1 reference)
"In 2022, two new classifications of myeloid neoplasms and acute leukemias were published: the 5th edition WHO Classification (WHO-HAEM5) and the International Consensus Classification (ICC)."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Momelotinib – a promising advancement in the management of myelofibrosis in adults with anemia
1 finding
Myelofibrosis (MF) is a rare BCR-ABL negative myeloproliferative neoplasm characterized by clonal proliferation of stem cells, with mutations in JAK2, CALR, or MPL genes.
"Myelofibrosis (MF) is a rare BCR-ABL negative myeloproliferative neoplasm characterized by clonal proliferation of stem cells, with mutations in JAK2, CALR, or MPL genes."
Show evidence (1 reference)
DOI:10.3389/fonc.2024.1411972 SUPPORT Human Clinical
"Myelofibrosis (MF) is a rare BCR-ABL negative myeloproliferative neoplasm characterized by clonal proliferation of stem cells, with mutations in JAK2, CALR, or MPL genes."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Association of Myelofibrosis Phenotypes with Clinical Manifestations, Molecular Profiles, and Treatments
1 finding
Myelofibrosis (MF) presents an array of clinical manifestations and molecular profiles.
"Myelofibrosis (MF) presents an array of clinical manifestations and molecular profiles."
Show evidence (1 reference)
DOI:10.3390/cancers15133331 SUPPORT Human Clinical
"Myelofibrosis (MF) presents an array of clinical manifestations and molecular profiles."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
A Prognostic Model to Predict Ruxolitinib Discontinuation and Death in Patients with Myelofibrosis
1 finding
Most patients with myelofibrosis (MF) discontinue ruxolitinib (JAK1/JAK2 inhibitor) in the first 5 years of therapy due to therapy failure.
"Most patients with myelofibrosis (MF) discontinue ruxolitinib (JAK1/JAK2 inhibitor) in the first 5 years of therapy due to therapy failure."
Show evidence (1 reference)
DOI:10.3390/cancers15205027 SUPPORT Human Clinical
"Most patients with myelofibrosis (MF) discontinue ruxolitinib (JAK1/JAK2 inhibitor) in the first 5 years of therapy due to therapy failure."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Real-World Electronic Medical Records Data Identify Risk Factors for Myelofibrosis and Can Be Used to Validate Established Prognostic Scores
1 finding
Myelofibrosis (MF) is a myeloproliferative neoplasia arising de novo as primary myelofibrosis (PMF) or secondary to polycythemia vera or essential thrombocythemia.
"Myelofibrosis (MF) is a myeloproliferative neoplasia arising de novo as primary myelofibrosis (PMF) or secondary to polycythemia vera or essential thrombocythemia."
Show evidence (1 reference)
DOI:10.3390/cancers16071416 SUPPORT Human Clinical
"Myelofibrosis (MF) is a myeloproliferative neoplasia arising de novo as primary myelofibrosis (PMF) or secondary to polycythemia vera or essential thrombocythemia."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Biological Markers of Myeloproliferative Neoplasms in Children, Adolescents and Young Adults
1 finding
Myeloproliferative neoplasms (MPNs) are clonal hematopoietic cancers characterized by hyperproliferation of the myeloid lineages.
"Myeloproliferative neoplasms (MPNs) are clonal hematopoietic cancers characterized by hyperproliferation of the myeloid lineages."
Show evidence (1 reference)
DOI:10.3390/cancers16234114 SUPPORT Human Clinical
"Myeloproliferative neoplasms (MPNs) are clonal hematopoietic cancers characterized by hyperproliferation of the myeloid lineages."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Current Advances in the Diagnosis and Treatment of Major Myeloproliferative Neoplasms
1 finding
Myeloproliferative neoplasms (MPNs) are a group of rare blood cancers characterized by the excessive production of blood cells in the bone marrow.
"Myeloproliferative neoplasms (MPNs) are a group of rare blood cancers characterized by the excessive production of blood cells in the bone marrow."
Show evidence (1 reference)
"Myeloproliferative neoplasms (MPNs) are a group of rare blood cancers characterized by the excessive production of blood cells in the bone marrow."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Myelofibrosis: Treatment Options After Ruxolitinib Failure
1 finding
Myelofibrosis: Treatment Options After Ruxolitinib Failure
"While allogeneic hematopoietic stem cell transplantation remains the only curative therapy for patients with myelofibrosis, its applicability is limited both by the high morbidity and mortality associated with the procedure and by the fact that only a minority of patients are eligible due to age..."
Show evidence (1 reference)
DOI:10.3390/curroncol32060339 SUPPORT Human Clinical
"While allogeneic hematopoietic stem cell transplantation remains the only curative therapy for patients with myelofibrosis, its applicability is limited both by the high morbidity and mortality associated with the procedure and by the fact that only a minority of patients are eligible due to age..."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.
Treatment Strategies Used in Treating Myelofibrosis: State of the Art
1 finding
Current drug therapy for myelofibrosis does not alter the natural course of the disease or prolong survival, and allogeneic stem cell transplantation is the only curative treatment modality.
"Current drug therapy for myelofibrosis does not alter the natural course of the disease or prolong survival, and allogeneic stem cell transplantation is the only curative treatment modality."
Show evidence (1 reference)
DOI:10.3390/hematolrep16040067 SUPPORT Human Clinical
"Current drug therapy for myelofibrosis does not alter the natural course of the disease or prolong survival, and allogeneic stem cell transplantation is the only curative treatment modality."
Deep research cited this publication as relevant literature for Primary Myelofibrosis.

Deep Research

1
Falcon
Primary Myelofibrosis (PMF): Disease Characteristics Research Report
Edison Scientific Literature 45 citations 2026-04-05T22:00:13.125717

Primary Myelofibrosis (PMF): Disease Characteristics Research Report

Target Disease

  • Disease name: Primary myelofibrosis (PMF)
  • Category: Philadelphia chromosome–negative (BCR::ABL1-negative) myeloproliferative neoplasm (MPN) (martino2024treatmentstrategiesused pages 1-2, wang2025currentadvancesin pages 5-7)
  • MONDO ID: Not reliably retrievable from the currently gathered evidence set (see “Identifiers” below). The MONDO ontology framework and identifier conventions are described in a general MONDO paper, but it does not provide a PMF-specific code in the retrieved text (vasilevsky2022; https://doi.org/10.1101/2022.04.13.22273750) (martino2024treatmentstrategiesused pages 2-4).

1. Disease Information

1.1 Concise overview (current understanding)

Primary myelofibrosis is a clonal hematopoietic stem/progenitor cell neoplasm characterized by atypical megakaryocytic (and granulocytic) proliferation, progressive bone marrow (BM) fibrosis, and extramedullary hematopoiesis (EMH), which collectively drive cytopenias, splenomegaly, constitutional symptoms, and risk of leukemic transformation (martino2024treatmentstrategiesused pages 1-2, wang2025currentadvancesin pages 5-7). A recent pathologic review describes PMF as a Ph-negative MPN featuring “clonal proliferation of atypical megakaryocytes and myeloid cells, fibrosis of the bone marrow, extramedullary hematopoiesis, and increased risk of leukemic transformation to acute myeloid leukemia (AML)” (abstract) (https://doi.org/10.3390/cancers18010050; 2025-12) (shao2025areviewof pages 4-6).

PMF includes a prefibrotic/early PMF stage (hypercellular marrow with minimal fibrosis) and overt/fibrotic-stage PMF with advanced fibrosis and leukoerythroblastosis (wang2025currentadvancesin pages 4-5, wang2025currentadvancesin pages 5-7).

1.2 Key identifiers and classifications

Because the current tool runs retrieved mostly primary literature and guideline-style reviews, ontology/administrative identifiers (ICD-10/ICD-11, MeSH, OMIM, Orphanet, MONDO) are not fully populated from the evidence captured here.

What can be stated from evidence: - Classification systems used clinically: WHO and ICC frameworks (WHO 5th edition/WHO-HAEM5; ICC 2022) are explicitly referenced in multiple sources for PMF/pre-PMF diagnosis and classification (https://doi.org/10.1007/s00277-025-06191-7; 2025-01) (wang2025currentadvancesin pages 5-7), and are discussed as contemporaneous classification systems (https://doi.org/10.1186/s13045-024-01571-4; 2024-07) (stuckey2025myelofibrosistreatmentoptions pages 8-10).

1.3 Common synonyms / alternative names

  • Primary myelofibrosis
  • PMF
  • “Overt PMF” (fibrotic stage) vs “prefibrotic PMF (pre-PMF)” (wang2025currentadvancesin pages 5-7, mora2024prognosticandpredictive pages 1-2)

1.4 Evidence provenance: individual vs aggregated resources

  • Many statements in this report derive from aggregated disease-level resources (reviews/guidelines) (martino2024treatmentstrategiesused pages 1-2, mora2024prognosticandpredictive pages 1-2, mclornan2023diagnosisandevaluation pages 6-6).
  • Real-world analyses explicitly use aggregated patient-level EHR/claims repositories (TriNetX; US payer claims). TriNetX analysis notes the database “includes more than 64,000 myelofibrosis patients” (https://doi.org/10.3390/cancers16071416; 2024-04) (martino2024treatmentstrategiesused pages 1-2). US claims analysis included “2830 patients with an MF diagnosis” and 1191 eligible for utilization/cost analysis (https://doi.org/10.1093/oncolo/oyab058; 2022-02) (martino2024treatmentstrategiesused pages 1-2).

2. Etiology

2.1 Disease causal factors (genetic/mechanistic)

PMF is driven by constitutive activation of the JAK–STAT signaling axis, typically via somatic driver mutations in JAK2, CALR, or MPL (chifotides2023associationofmyelofibrosis pages 2-4, wang2025currentadvancesin pages 5-7). A 2022 ASH Education review states MF is “universally driven by Jak/STAT pathway activation” (https://doi.org/10.1182/hematology.2022000340; 2022-12) (reynolds2022newapproachesto pages 1-3).

2.2 Risk factors

Genetic risk factors

  • Driver mutations and approximate frequencies (PMF):
    A 2023 phenotype-focused review reports PMF driver frequencies of ~60% JAK2 V617F, ~25–30% CALR exon 9, and ~5–10% MPL (W515L/K) (https://doi.org/10.3390/cancers15133331; 2023-06) (chifotides2023associationofmyelofibrosis pages 2-4).
    A 2024 prognostic review provides another commonly cited distribution: “Two-thirds of patients with PMF harbor JAK2V617F, 25% CALR, and 10% each MPL or no driver mutation (‘triple negative’ status, TN)” (abstract) (https://doi.org/10.1007/s11899-024-00739-6; 2024-08) (mora2024prognosticandpredictive pages 1-2).
  • High molecular risk (HMR) mutations: HMR mutations commonly include ASXL1, EZH2, IDH1, IDH2, SRSF2 and U2AF1 Q157 (chifotides2023associationofmyelofibrosis pages 2-4, mclornan2023diagnosisandevaluation pages 6-6). The 2024 prognostic review defines HMR as “ASXL1, SRSF2, EZH2, and IDH1/IDH2” and links them to worse OS/blast-phase risk (mora2024prognosticandpredictive pages 1-2).

Environmental/host risk factors

Specific exogenous environmental causes (toxins, infections, etc.) were not identified in the retrieved evidence snippets. Host factors associated with outcomes/complications in real-world datasets include age and blood count abnormalities (martino2024treatmentstrategiesused pages 1-2, reynolds2022newapproachesto pages 1-3).

2.3 Protective factors

No specific genetic or environmental protective factors were captured in the current evidence set.

2.4 Gene–environment interactions

No PMF-specific gene–environment interaction evidence was captured in the current evidence set.


3. Phenotypes

3.1 Core clinical manifestations and laboratory abnormalities

PMF exhibits heterogeneous presentation; ~25–33% can be asymptomatic initially (shao2025areviewof pages 4-6). Common manifestations include: - Splenomegaly (often marked), due to EMH (shao2025areviewof pages 4-6, wang2025currentadvancesin pages 5-7) - Anemia and progressive cytopenias (shao2025areviewof pages 4-6, wang2025currentadvancesin pages 5-7) - Leukoerythroblastosis and teardrop RBCs (peripheral smear) (shao2025areviewof pages 4-6) - Constitutional symptoms (fever, weight loss, night sweats) and cachexia (wang2025currentadvancesin pages 5-7) - Thrombosis/bleeding: a pathology review reports “Thromboembolic events occur in ~10–20% of patients” (https://doi.org/10.3390/cancers18010050; 2025-12) (shao2025areviewof pages 4-6).

3.2 Phenotype subtypes (proliferative vs cytopenic)

Two clinically meaningful ends of a spectrum are highlighted: - Myeloproliferative phenotype: larger spleens, leukocytosis, normal/higher counts or mild anemia; fewer non-driver mutations and higher JAK2 allele burden; generally better response to ruxolitinib (chifotides2023associationofmyelofibrosis pages 2-4). - Myelodepletive/cytopenic phenotype: ≥2 cytopenias, transfusion dependence, modest splenomegaly; more HMR mutations and genomic complexity; inferior outcomes; emphasizes less myelosuppressive JAK inhibitors (momelotinib/pacritinib) (chifotides2023associationofmyelofibrosis pages 2-4, reynolds2022newapproachesto pages 1-3).

3.3 Phenotype characteristics (age of onset, progression, frequency)

  • Typical onset: older adults; median age around the 7th decade (mora2024prognosticandpredictive pages 1-2). One review reports median age at diagnosis ~65 (martino2024treatmentstrategiesused pages 1-2).
  • Progression: prefibrotic → overt fibrotic stage with worsening cytopenias and EMH; risk of accelerated/blast phase exists (wang2025currentadvancesin pages 4-5, wang2025currentadvancesin pages 5-7).

3.4 Quality-of-life impact

Quality of life is impacted by anemia, constitutional symptoms, and splenomegaly; treatment goals emphasize symptom and spleen improvement (martino2024treatmentstrategiesused pages 1-2, wang2025currentadvancesin pages 5-7).

3.5 Suggested HPO terms (examples)

  • Splenomegaly HP:0001744
  • Anemia HP:0001903
  • Thrombocytopenia HP:0001873
  • Leukocytosis HP:0001974
  • Leukoerythroblastosis HP:0032465 (term exists in HPO; verify exact ID in implementation)
  • Constitutional symptoms: Fever HP:0001945, Weight loss HP:0001824, Night sweats HP:0030166, Fatigue HP:0012378
  • Bone marrow fibrosis HP:0010984 (term exists; verify in implementation)

4. Genetic / Molecular Information

4.1 Causal genes (somatic driver genes)

  • JAK2, CALR, MPL are canonical driver genes activating JAK–STAT signaling in PMF (chifotides2023associationofmyelofibrosis pages 2-4, wang2025currentadvancesin pages 5-7).

4.2 Pathogenic variants (typical PMF)

  • JAK2 p.V617F (somatic), and MPL W515 variants (e.g., W515L/K), and CALR exon 9 frameshift variants are repeatedly referenced as drivers (chifotides2023associationofmyelofibrosis pages 2-4, mora2024prognosticandpredictive pages 1-2).

4.3 Modifier/cooperating mutations and prognostic genomics

  • Non-driver myeloid gene variants are common: “About 80% of PMF … cases carry [myeloid gene variants]” (https://doi.org/10.1007/s11899-024-00739-6; 2024-08) (mora2024prognosticandpredictive pages 1-2).
  • Frequently discussed genes include epigenetic regulators and splicing factors (DNMT3A, TET2, ASXL1, SRSF2, U2AF1, EZH2, IDH1/2, TP53) (mora2024prognosticandpredictive pages 1-2).

4.4 Epigenetic information

The current evidence set supports that epigenetic regulators (e.g., ASXL1, DNMT3A, EZH2, TET2) are common co-mutations and carry prognostic relevance, but does not provide direct disease-specific methylation/histone profiling datasets (mora2024prognosticandpredictive pages 1-2).

4.5 Chromosomal abnormalities

A pathology review notes karyotypic abnormalities in up to ~45% of cases; common abnormalities include del(20q), del(13q), +8, +9 (shao2025areviewof pages 4-6). Another review gives a similar range (~30–50%) and lists del(13q), del(20q), +8, +9, del(12p), trisomy 1q (ozygała2024biologicalmarkersof pages 10-12).


5. Environmental Information

  • Environmental factors / lifestyle / infectious agents: Not specifically identified in the retrieved evidence snippets for PMF etiology. PMF is primarily characterized in the retrieved literature as a clonal neoplasm with somatic driver mutations and inflammatory/fibrotic microenvironment changes (shao2025areviewof pages 4-6, chifotides2023associationofmyelofibrosis pages 2-4).

6. Mechanism / Pathophysiology

6.1 Core causal chain (integrated)

1) Somatic driver mutation (JAK2/CALR/MPL) in hematopoietic stem/progenitor cells → constitutive JAK–STAT signaling (chifotides2023associationofmyelofibrosis pages 2-4, reynolds2022newapproachesto pages 1-3).
2) Expansion/dysregulation of myeloid lineages with atypical megakaryocytes → secretion of pro-inflammatory/pro-fibrotic mediators (IL-1β, TGF-β; PDGF, VEGF, b-FGF) (wang2025currentadvancesin pages 5-7).
3) Bone marrow microenvironment remodeling and activation of stromal programs → progressive reticulin/collagen fibrosis and ineffective hematopoiesis (martino2024treatmentstrategiesused pages 1-2, wang2025currentadvancesin pages 5-7).
4) BM failure drives EMH in spleen/liver and systemic symptoms (shao2025areviewof pages 4-6, wang2025currentadvancesin pages 5-7).

6.2 Fibrosis biology and cell types

A pathology review states fibrosis is driven by profibrotic cytokines including “TGF-β, PDGF, VEGF” and implicates Gli1+ and Lepr+ mesenchymal stem cell populations in fibrotic remodeling, alongside pathways such as BMP/Wnt (shao2025areviewof pages 4-6).

6.3 Anemia biology and hepcidin/ACVR1 axis (therapeutically actionable)

Anemia is a hallmark and negative prognostic factor (mora2024prognosticandpredictive pages 1-2, reynolds2022newapproachesto pages 1-3). ACVR1 (ALK2) inhibition is used therapeutically to suppress hepcidin signaling and improve iron-restricted anemia; momelotinib is a JAK1/2 and ACVR1 inhibitor whose “dual inhibition mechanism addresses anemia by suppressing hepcidin production” (review abstract) (https://doi.org/10.3389/fonc.2024.1411972; 2024-06) (chifotides2023associationofmyelofibrosis pages 2-4).

6.4 Suggested ontology terms

GO Biological Process (examples): - “JAK-STAT cascade” (GO term; verify exact ID in implementation) - “Cytokine-mediated signaling pathway” - “Extracellular matrix organization” - “Collagen fibril organization” - “Hepcidin metabolic process” - “Inflammatory response”

Cell Ontology (CL) (examples): - Megakaryocyte (CL:0000554) - Hematopoietic stem cell (CL:0000037) - Mesenchymal stromal cell / mesenchymal stem cell (term exists; verify exact CL ID)


7. Anatomical Structures Affected

7.1 Organ/tissue targets

  • Primary: bone marrow (site of clonal proliferation and fibrosis) (martino2024treatmentstrategiesused pages 1-2, wang2025currentadvancesin pages 5-7)
  • Secondary: spleen and liver (EMH causing hepatosplenomegaly) (shao2025areviewof pages 4-6, wang2025currentadvancesin pages 5-7)

7.2 Suggested anatomy ontology (UBERON examples)

  • Bone marrow UBERON:0002371
  • Spleen UBERON:0002106
  • Liver UBERON:0002107

8. Temporal Development

8.1 Onset

  • Typically adult/older adult onset (median onset in 7th decade) (mora2024prognosticandpredictive pages 1-2).

8.2 Progression patterns

  • Prefibrotic PMF → overt PMF (fibrotic stage) is a recognized evolution in WHO/ICC conceptualization (wang2025currentadvancesin pages 4-5, wang2025currentadvancesin pages 5-7).
  • Accelerated phase (10–19% blasts) and blast phase (≥20% blasts) define progression to high-grade disease; blast-phase MPN incidence estimates include 9–13% for PMF in a contemporary review (https://doi.org/10.1038/s41408-023-00878-8; 2023-07) (wang2025currentadvancesin pages 4-5).

9. Inheritance and Population

9.1 Epidemiology

  • Incidence:
  • A 2024 review reports annual incidence range 0.22–0.99 per 100,000 (with regional examples North America 0.33–0.46; Europe 0.1–1) and male predominance (martino2024treatmentstrategiesused pages 1-2).
  • A 2024 prognostic review gives a US incidence estimate of 0.44 per 100,000 per year (mora2024prognosticandpredictive pages 1-2).
  • Age/sex: median diagnosis around 65 and onset commonly in 7th decade; incidence higher in men than women in one review (martino2024treatmentstrategiesused pages 1-2, mora2024prognosticandpredictive pages 1-2).

9.2 Inheritance

PMF is principally a somatic clonal neoplasm in the retrieved evidence set; germline Mendelian inheritance patterns are not emphasized in these sources.


10. Diagnostics

10.1 Diagnostic criteria (WHO/ICC-aligned) and key concepts

Multiple sources converge on a major + minor criteria framework: - A 2023 British Society for Haematology guideline states: “Diagnosis requires all three major criteria and at least one minor criterion confirmed in two consecutive determinations.” (https://doi.org/10.1111/bjh.19164; 2023-11) (mclornan2023diagnosisandevaluation pages 6-6). - A 2024 review similarly summarizes diagnostic structure and provides a detailed minor-criteria list (anemia not due to comorbidity, leukocytosis ≥11×10^9/L, palpable splenomegaly, elevated LDH, leukoerythroblastosis) (martino2024treatmentstrategiesused pages 2-4).

Core diagnostic elements supported by evidence: - Bone marrow morphology: megakaryocytic proliferation/atypia and grading of fibrosis (pre-PMF ≤MF-1; overt PMF MF-2/3) (shao2025areviewof pages 4-6, wang2025currentadvancesin pages 5-7). - Clonality evidence: JAK2/CALR/MPL driver mutation or other clonal marker (martino2024treatmentstrategiesused pages 2-4, mclornan2023diagnosisandevaluation pages 6-6). - Exclusion of other myeloid neoplasms (including BCR::ABL1-positive CML) (martino2024treatmentstrategiesused pages 2-4, wang2025currentadvancesin pages 5-7).

10.2 Testing modalities

  • Driver mutation detection and broader NGS panels are integral; ICC-oriented review emphasizes sensitive techniques and notes “high sensitive single target (RT-qPCR, ddPCR) or multi-target next-generation sequencing assays with a minimal sensitivity of VAF 1% are now important for a proper diagnostic identification of MPN cases with low allelic frequencies at initial presentation” (https://doi.org/10.1007/s00428-022-03480-8; 2023-12) (wang2025currentadvancesin pages 5-7).

10.3 Differential diagnosis (high level)

  • Essential thrombocythemia (ET), polycythemia vera (PV), secondary myelofibrosis (post-PV/post-ET), and other myeloid neoplasms must be excluded; this is explicitly embedded in major criteria summaries (martino2024treatmentstrategiesused pages 2-4, wang2025currentadvancesin pages 5-7).

11. Outcome / Prognosis

11.1 Survival and mortality (risk-stratified)

Prognosis is heterogeneous and is commonly modeled using clinical, cytogenetic, and molecular risk systems. - A 2024 prognostic review provides median OS estimates by MF subtype: “Median overall survival (OS) of pre-PMF, overt-PMF and SMF patients is around 14 years, seven and nine years, respectively.” (abstract) (https://doi.org/10.1007/s11899-024-00739-6; 2024-08) (mora2024prognosticandpredictive pages 1-2). - Risk scores (IPSS/DIPSS/DIPSS-plus) span median OS approximately from ~11.3 years (low risk) to ~2.3 years (high risk) in one review summary (mora2024prognosticandpredictive pages 1-2). Another review provides representative medians by IPSS and DIPSS-plus categories (martino2024treatmentstrategiesused pages 2-4).

11.2 Prognostic factors

Common adverse features include older age, leukocytosis, anemia, thrombocytopenia, circulating blasts, constitutional symptoms, unfavorable karyotype, and HMR mutations (martino2024treatmentstrategiesused pages 2-4, mora2024prognosticandpredictive pages 1-2).

11.3 Prognostic models used clinically

  • IPSS (at diagnosis), DIPSS (dynamic), DIPSS-plus (adds transfusion dependence, platelet count, karyotype), and molecularly informed models MIPSS70+ v2.0 and GIPSS are described across sources (martino2024treatmentstrategiesused pages 2-4, mora2024prognosticandpredictive pages 1-2, mclornan2023diagnosisandevaluation pages 6-6).
  • BSH highlights MIPSS70+ v2.0 integration of karyotype and mutations including U2AF1 Q157 and notes it is “more accurate than IPSS” in its derivation cohort (mclornan2023diagnosisandevaluation pages 6-6).

12. Treatment

12.1 Treatment goals and real-world implementation

Goals emphasize symptom control and spleen volume reduction; transplantation is reserved for selected higher-risk patients (martino2024treatmentstrategiesused pages 1-2, martino2024treatmentstrategiesused pages 2-4). A 2024 review states: “Current drug therapy for myelofibrosis does not alter the natural course of the disease or prolong survival, and allogeneic stem cell transplantation is the only curative treatment modality.” (abstract) (https://doi.org/10.3390/hematolrep16040067; 2024-10) (martino2024treatmentstrategiesused pages 1-2).

12.2 Pharmacotherapy (JAK inhibitors and anemia-directed strategies)

Ruxolitinib (JAK1/2 inhibitor)

  • Standard-of-care for intermediate/high-risk MF for spleen and symptom benefit (martino2024treatmentstrategiesused pages 1-2, stuckey2025myelofibrosistreatmentoptions pages 8-10).
  • Real-world discontinuation is common: a 2023 Italian real-world analysis states in its abstract, “50% to 70% of patients discontinue ruxolitinib within 3 to 5 years” (https://doi.org/10.3390/cancers15205027; 2023-10) (wang2025currentadvancesin pages 5-7).

Momelotinib (JAK1/2 + ACVR1/ALK2 inhibitor; anemia benefit; FDA approval 2023-09-15)

  • A 2024 expert commentary notes momelotinib was “recently approved (September 15, 2023) for use in anemic patients with high/intermediate risk myelofibrosis (MF), including primary (PMF)” (https://doi.org/10.1038/s41408-024-01029-3; 2024-03) (chifotides2023associationofmyelofibrosis pages 2-4).
  • SIMPLIFY-2 subgroup analysis (JAK inhibitor-experienced, anemia focus): week-24 transfusion independence (TI) was higher with momelotinib vs best available therapy/continued ruxolitinib: 33.3% vs 12.8% in baseline Hb <100 g/L subgroup, and 34.7% vs 3.0% in baseline non–transfusion-independent subgroup (https://doi.org/10.1007/s12325-024-02928-4; 2024-07) (wang2025currentadvancesin pages 5-7).

Pacritinib (JAK2/IRAK1/ACVR1; JAK1-sparing; thrombocytopenic MF)

  • ASH Education Program review: “Pacritinib, selective Jak2 inhibitor, was approved in 2022 to treat patients with symptomatic MF and a platelet count lower than 50 × 10^9/L.” (https://doi.org/10.1182/hematology.2022000340; 2022-12) (reynolds2022newapproachesto pages 1-3).
  • Real-world effectiveness in bicytopenic MF (community oncology EHR, 2022–2023): Among bicytopenic patients, median platelets improved from 61.0×10^9/L at index to 68.0×10^9/L at day 90; median hemoglobin improved from 7.2 g/dL at index to 8.0 g/dL at day 90; 6-month OS 77.8% (Blood 2024 abstract; https://doi.org/10.1182/blood-2024-210274) (stuckey2025myelofibrosistreatmentoptions pages 8-10).

12.3 Allogeneic hematopoietic stem cell transplantation (allo-HSCT)

Allo-HSCT is repeatedly stated as the only curative option, generally for transplant-eligible higher-risk patients (martino2024treatmentstrategiesused pages 1-2, stuckey2025myelofibrosistreatmentoptions pages 8-10). (A detailed 2024 EBMT/ELN transplant guideline was not obtainable in this run, so granular transplant outcome statistics cannot be quoted here.)

12.4 Supportive care and symptom measurement implementation

  • Symptom endpoints in pivotal trials often use MPN-SAF / MFSAF Total Symptom Score (TSS) reduction thresholds (TSS50), which have become regulatory endpoints and are used increasingly in practice (https://doi.org/10.1007/s10238-025-01830-9; 2025) (wang2025currentadvancesin pages 5-7).

12.5 MAXO (Medical Action Ontology) suggestions (examples)

  • JAK inhibitor therapy (e.g., ruxolitinib, fedratinib, momelotinib, pacritinib)
  • Allogeneic hematopoietic stem cell transplantation
  • Red blood cell transfusion
  • Symptom assessment/monitoring with validated PRO instruments

13. Prevention

No established primary prevention strategies are identified in the retrieved evidence, consistent with PMF being largely a sporadic somatic neoplasm in most clinical contexts. Secondary/tertiary prevention focuses on monitoring, symptom control, transfusion support, thrombosis/bleeding management, and preventing/mitigating progression via risk-adapted therapy (martino2024treatmentstrategiesused pages 2-4, mclornan2023diagnosisandevaluation pages 6-6).


14. Other Species / Natural Disease

No naturally occurring PMF in non-human species was captured in the retrieved evidence snippets.


15. Model Organisms

The retrieved evidence references stromal-cell involvement and fibrosis pathways (e.g., Gli1+ and Lepr+ mesenchymal stem cells) as part of mechanistic understanding, but does not provide specific PMF model organism systems in the captured snippets (shao2025areviewof pages 4-6).


Recent developments (2023–2024 highlights)

1) Expanded therapeutic landscape for cytopenic/anemic MF: momelotinib approval (2023-09-15) and anemia-focused evidence (SIMPLIFY-2 subgroup TI improvements) (chifotides2023associationofmyelofibrosis pages 2-4, wang2025currentadvancesin pages 5-7).
2) Real-world data scaling using EHR networks: TriNetX-based MF studies spanning >64,000 MF patients to validate risk factors and simplified IPSS approaches (https://doi.org/10.3390/cancers16071416; 2024-04) (martino2024treatmentstrategiesused pages 1-2).
3) Modern prognostication: emphasis on mutation-informed models (MIPSS70+ v2.0) and integrated risk modeling (mora2024prognosticandpredictive pages 1-2, mclornan2023diagnosisandevaluation pages 6-6).
4) Recognition of phenotypic heterogeneity (proliferative vs cytopenic): linking clinical phenotype with allele burden and co-mutation architecture to tailor therapy (chifotides2023associationofmyelofibrosis pages 2-4, reynolds2022newapproachesto pages 1-3).


Key statistics (selected, recent)

  • PMF incidence range 0.22–0.99 per 100,000 per year (review) (martino2024treatmentstrategiesused pages 1-2).
  • US incidence estimate 0.44 per 100,000 per year (mora2024prognosticandpredictive pages 1-2).
  • Driver distribution in PMF: ~60% JAK2 / 25–30% CALR / 5–10% MPL (chifotides2023associationofmyelofibrosis pages 2-4) or ~two-thirds JAK2 / 25% CALR / 10% MPL / 10% triple-negative (mora2024prognosticandpredictive pages 1-2).
  • Thromboembolic events ~10–20% (shao2025areviewof pages 4-6).
  • Ruxolitinib discontinuation: 50–70% within 3–5 years (abstract statement) (wang2025currentadvancesin pages 5-7).
  • SIMPLIFY-2 anemia-focused subgroup: TI at week 24 up to 33.3% vs 12.8% (Hb<100 g/L) and 34.7% vs 3.0% (baseline non-TI) for momelotinib vs BAT/ruxolitinib (wang2025currentadvancesin pages 5-7).

Embedded summary table: molecular hallmarks

Feature category PMF finding Approximate frequency / definition Clinical or biologic association
Driver mutation JAK2 V617F ~60% of PMF; alternatively described as about two-thirds of PMF (chifotides2023associationofmyelofibrosis pages 2-4, mora2024prognosticandpredictive pages 1-2) Higher allele burden is associated with the myeloproliferative phenotype; lower burden with myelodepletive/cytopenic phenotype (chifotides2023associationofmyelofibrosis pages 2-4)
Driver mutation CALR exon 9 ~25–30% of PMF; another source gives ~25% (chifotides2023associationofmyelofibrosis pages 2-4, mora2024prognosticandpredictive pages 1-2) CALR is a major clonal driver used in diagnosis; type 1/like CALR is incorporated in molecular prognostic models such as MIPSS70 (martino2024treatmentstrategiesused pages 2-4, mora2024prognosticandpredictive pages 1-2)
Driver mutation MPL (classically W515L/K) ~5–10% of PMF; another source gives ~10% (chifotides2023associationofmyelofibrosis pages 2-4, mora2024prognosticandpredictive pages 1-2) Canonical MPN driver used in WHO/ICC-style diagnostic workup (martino2024treatmentstrategiesused pages 2-4, mclornan2023diagnosisandevaluation pages 6-6)
Driver-negative subset Triple-negative PMF ~10% in one review; ~10–15% in another broader MPN review (mora2024prognosticandpredictive pages 1-2, ozygała2024biologicalmarkersof pages 10-12) Generally considered biologically adverse in PMF literature; requires other clonal evidence/exclusion of reactive fibrosis in diagnostic frameworks (mclornan2023diagnosisandevaluation pages 6-6, ozygała2024biologicalmarkersof pages 10-12)
High molecular risk (HMR) definition ASXL1, EZH2, IDH1, IDH2, SRSF2, U2AF1 Q157 HMR genes are the adverse mutation set used in contemporary prognostic models; BSH notes MIPSS70+ v2.0 incorporates HMR genes plus U2AF1 Q157 (chifotides2023associationofmyelofibrosis pages 2-4, mclornan2023diagnosisandevaluation pages 6-6) Associated with worse overall survival, higher blast-phase risk, and more aggressive biology (chifotides2023associationofmyelofibrosis pages 2-4, mora2024prognosticandpredictive pages 1-2)
Common co-mutations ASXL1, DNMT3A, TET2 Co-mutations occur in ~50% of patients; ASXL1, DNMT3A, and TET2 are repeatedly cited as common examples (martino2024treatmentstrategiesused pages 2-4) Reflect clonal complexity and are relevant to prognosis beyond driver status (martino2024treatmentstrategiesused pages 2-4, mora2024prognosticandpredictive pages 1-2)
Additional recurrent co-mutations SRSF2, EZH2, IDH1/2, SF3B1, U2AF1, TP53 About 80% of PMF cases carry non-driver myeloid gene variants in one 2024 review (mora2024prognosticandpredictive pages 1-2) Splicing/epigenetic mutations are enriched in advanced or cytopenic disease and shorten survival (chifotides2023associationofmyelofibrosis pages 2-4, mora2024prognosticandpredictive pages 1-2)
Mutations linked to advanced disease ASXL1, U2AF1-Q157, SRSF2 Not primarily frequency-defined here, but identified as enriched in MF/advanced disease (martino2024treatmentstrategiesused pages 2-4) Poorer survival and adverse-risk enrichment (martino2024treatmentstrategiesused pages 2-4, wang2025currentadvancesin pages 5-7)
Mutations linked to treatment resistance RAS/CBL pathway mutations Defined as non-driver adverse co-mutations rather than frequent drivers (martino2024treatmentstrategiesused pages 2-4, wang2025currentadvancesin pages 5-7) Associated with ruxolitinib resistance/failure (martino2024treatmentstrategiesused pages 2-4, wang2025currentadvancesin pages 5-7)
Phenotype association Myeloproliferative phenotype Molecular profile tends to show higher JAK2 V617F burden and fewer non-driver mutations (chifotides2023associationofmyelofibrosis pages 2-4) Typical features: larger spleen, leukocytosis, normal/mild anemia, lower fibrosis grade, better response to ruxolitinib (chifotides2023associationofmyelofibrosis pages 2-4)
Phenotype association Myelodepletive / cytopenic phenotype More often shows lower JAK2 V617F burden, greater genomic complexity, and more HMR/splicing-epigenetic mutations (chifotides2023associationofmyelofibrosis pages 2-4, reynolds2022newapproachesto pages 1-3) Typical features: ≥2 cytopenias, transfusion dependence, moderate/severe thrombocytopenia, higher fibrosis grade, inferior survival, limited ruxolitinib response; non-myelosuppressive JAK inhibitors (momelotinib/pacritinib) are emphasized for this phenotype (chifotides2023associationofmyelofibrosis pages 2-4, reynolds2022newapproachesto pages 1-3)

Table: This table summarizes the core genetic and molecular hallmarks of primary myelofibrosis, including driver mutation frequencies, adverse co-mutation profiles, and how molecular features map to myeloproliferative versus myelodepletive phenotypes. It is useful as a compact reference for diagnosis, prognosis, and treatment stratification.


Source URLs (selected)

  • Martino et al., Hematology Reports (2024-10): https://doi.org/10.3390/hematolrep16040067 (martino2024treatmentstrategiesused pages 1-2)
  • Mora et al., Curr Hematol Malig Rep (2024-08): https://doi.org/10.1007/s11899-024-00739-6 (mora2024prognosticandpredictive pages 1-2)
  • Chifotides et al., Cancers (2023-06): https://doi.org/10.3390/cancers15133331 (chifotides2023associationofmyelofibrosis pages 2-4)
  • McLornan et al., BSH Guideline (Br J Haematol) (2023-11): https://doi.org/10.1111/bjh.19164 (mclornan2023diagnosisandevaluation pages 6-6)
  • Harrison et al., SIMPLIFY-2 subgroup (Adv Ther) (2024-07): https://doi.org/10.1007/s12325-024-02928-4 (wang2025currentadvancesin pages 5-7)
  • Reynolds & Pettit, ASH Education (2022-12): https://doi.org/10.1182/hematology.2022000340 (reynolds2022newapproachesto pages 1-3)

References

  1. (martino2024treatmentstrategiesused pages 1-2): Massimo Martino, Martina Pitea, Annalisa Sgarlata, Ilaria Maria Delfino, Francesca Cogliandro, Anna Scopelliti, Violetta Marafioti, Simona Polimeni, Gaetana Porto, Giorgia Policastro, Giovanna Utano, Maria Pellicano, Giovanni Leanza, and Caterina Alati. Treatment strategies used in treating myelofibrosis: state of the art. Hematology Reports, 16:698-713, Oct 2024. URL: https://doi.org/10.3390/hematolrep16040067, doi:10.3390/hematolrep16040067. This article has 4 citations.

  2. (wang2025currentadvancesin pages 5-7): Le Wang, Julie Li, Leah Arbitman, Hailing Zhang, Haipeng Shao, Michael Martin, Lynn Moscinski, and Jinming Song. Current advances in the diagnosis and treatment of major myeloproliferative neoplasms. Cancers, 17:1834, May 2025. URL: https://doi.org/10.3390/cancers17111834, doi:10.3390/cancers17111834. This article has 5 citations.

  3. (martino2024treatmentstrategiesused pages 2-4): Massimo Martino, Martina Pitea, Annalisa Sgarlata, Ilaria Maria Delfino, Francesca Cogliandro, Anna Scopelliti, Violetta Marafioti, Simona Polimeni, Gaetana Porto, Giorgia Policastro, Giovanna Utano, Maria Pellicano, Giovanni Leanza, and Caterina Alati. Treatment strategies used in treating myelofibrosis: state of the art. Hematology Reports, 16:698-713, Oct 2024. URL: https://doi.org/10.3390/hematolrep16040067, doi:10.3390/hematolrep16040067. This article has 4 citations.

  4. (shao2025areviewof pages 4-6): Richard Shao, Christopher Ryder, Le Wang, Hailing Zhang, Lynn Moscinski, Michael Martin, Mac Shebes, Julie Y. Li, and Jinming Song. A review of the pathological and molecular diagnosis of primary myelofibrosis. Cancers, 18:50, Dec 2025. URL: https://doi.org/10.3390/cancers18010050, doi:10.3390/cancers18010050. This article has 0 citations.

  5. (wang2025currentadvancesin pages 4-5): Le Wang, Julie Li, Leah Arbitman, Hailing Zhang, Haipeng Shao, Michael Martin, Lynn Moscinski, and Jinming Song. Current advances in the diagnosis and treatment of major myeloproliferative neoplasms. Cancers, 17:1834, May 2025. URL: https://doi.org/10.3390/cancers17111834, doi:10.3390/cancers17111834. This article has 5 citations.

  6. (stuckey2025myelofibrosistreatmentoptions pages 8-10): Ruth Stuckey, Adrián Segura Díaz, and María Teresa Gómez-Casares. Myelofibrosis: treatment options after ruxolitinib failure. Current Oncology, 32:339, Jun 2025. URL: https://doi.org/10.3390/curroncol32060339, doi:10.3390/curroncol32060339. This article has 2 citations.

  7. (mora2024prognosticandpredictive pages 1-2): Barbara Mora, Cristina Bucelli, Daniele Cattaneo, Valentina Bellani, Francesco Versino, Kordelia Barbullushi, Nicola Fracchiolla, Alessandra Iurlo, and Francesco Passamonti. Prognostic and predictive models in myelofibrosis. Current Hematologic Malignancy Reports, 19:223-235, Aug 2024. URL: https://doi.org/10.1007/s11899-024-00739-6, doi:10.1007/s11899-024-00739-6. This article has 16 citations.

  8. (mclornan2023diagnosisandevaluation pages 6-6): Donal P. McLornan, Anna L. Godfrey, Anna Green, Rebecca Frewin, Siamak Arami, Jessica Brady, Nauman M. Butt, Catherine Cargo, Joanne Ewing, Sebastian Francis, Mamta Garg, Claire Harrison, Andrew Innes, Alesia Khan, Steve Knapper, Jonathan Lambert, Adam Mead, Andrew McGregor, Pratap Neelakantan, Bethan Psaila, Tim C. P. Somervaille, Claire Woodley, Jyoti Nangalia, Nicholas C. P. Cross, and Mary Frances McMullin. Diagnosis and evaluation of prognosis of myelofibrosis: a british society for haematology guideline. British Journal of Haematology, 204:127-135, Nov 2023. URL: https://doi.org/10.1111/bjh.19164, doi:10.1111/bjh.19164. This article has 6 citations and is from a domain leading peer-reviewed journal.

  9. (chifotides2023associationofmyelofibrosis pages 2-4): Helen T. Chifotides, Srdan Verstovsek, and Prithviraj Bose. Association of myelofibrosis phenotypes with clinical manifestations, molecular profiles, and treatments. Cancers, 15:3331, Jun 2023. URL: https://doi.org/10.3390/cancers15133331, doi:10.3390/cancers15133331. This article has 27 citations.

  10. (reynolds2022newapproachesto pages 1-3): Samuel B. Reynolds and Kristen Pettit. New approaches to tackle cytopenic myelofibrosis. Hematology. American Society of Hematology. Education Program, 2022 1:235-244, Dec 2022. URL: https://doi.org/10.1182/hematology.2022000340, doi:10.1182/hematology.2022000340. This article has 17 citations.

  11. (ozygała2024biologicalmarkersof pages 10-12): Aleksandra Ozygała, Joanna Rokosz-Mierzwa, Paulina Widz, Paulina Skowera, Mateusz Wiliński, Borys Styka, and Monika Lejman. Biological markers of myeloproliferative neoplasms in children, adolescents and young adults. Cancers, 16:4114, Dec 2024. URL: https://doi.org/10.3390/cancers16234114, doi:10.3390/cancers16234114. This article has 3 citations.