Myelofibrosis

Background

• Chronic myeloproliferative disorder
• Abnormal proliferation is seen in all 3 cell lines
• Typically in elderly
• Can be asymptomatic or symptomatic
• Can be primary or develop secondary to polycythemia vera or essential thrombocytosis

Clinical Features

• • Anemia
  • Pancytopenia (in late disease)
  • Palpable splenomegaly
  • Bone pain
  • Increased serum LDH

Differential Diagnosis

• Polycythemia vera (PV)
• Essential thrombocytosis (ET)
• Chronic myelogenous leukemia (CML)
• Leukemoid reactions

Evaluation

Workup

• CBC
• Blood smear
• Chem 7
• Bone marrow biopsy

Evaluation

• Criteria: The diagnosis of primary myelofibrosis requires meeting all 3 major criteria and 2 minor criteria.

Major criteria
Megakaryocyte proliferation and atypia with reticulin and/or collagen fibrosis, or with increased marrow cellularity, granulocytic proliferation, and decreased erythropoiesis
Not meeting WHO criteria for CML, PV, MDS, or other myeloid neoplasm
Demonstration of JAK2V617F or other clonal marker or no evidence of reactive bone marrow fibrosis

Minor criteria
Leukoerythroblastosis
Increased serum LDH
Anemia
Palpable splenomegaly

Management

• Blood transfusion
• Ruxolitinib
• Allogeneic stem cell transplantation