Marrow slowly replaced with reticulin and collagen
About
- Myeloproliferative disorders with bone marrow fibrosis
- A small percentage transform to AML
Aetiology
- Hyperplasia of megakaryocytes which release platelet derived growth factor which stimulates fibrosis
- Marrow fibrosis, myeloid metaplasia, extramedullary hematopoiesis, and
splenomegaly.
Clinical
- Fever, malaise, weight loss
- Massive Liver and Splenomegaly (extramedullary haemopoiesis)
- Can transform to an acute leukaemia
- Infection and organomegaly
Investigations
A leukoerythroblastic blood film with "teardrop" shaped cells
- Anaemia and Raised WCC but in late stages WCC falls. Raised platelets which later falls
- Blood film: teardrop-shaped red cells, immature myeloid cells, and abnormal platelets. Leukocytes and platelets may both be elevated
- No Philadelphia chromosome (differentiates it from CML)
- High urate, LAP - high or normal
Differential: Myelofibrosis vs CML
- Myelofibrosis - abnormal megakaryocyte precursors release a factor increasing localised fibrosis within the bone marrow. This leads to extramedullary haemopoiesis
- Myelofibrosis - absent Philadelphia chromosome but seen in CML
- Myelofibrosis - A leukoerythroblastic blood film with "teardrop" shaped cells
- Myelofibrosis - hepatosplenomegaly
- Myelofibrosis - high platelets and white cells which eventually falls and anaemia
- Myelofibrosis - possible high LAP score, Low in CML
Management
- Supportive - median survival 3 years
- Transfuse as needed + Folic acid
- Allopurinol to prevent gout
- Hydroxycarbamide/hydroxyurea
- Chemotherapy or local irradiation or Splenectomy to reduce spleen size
- Palliation with death from Infection, bleeding etc..