Myelofibrosis

Exam Cram

• Myelofibrosis is a bone marrow cancer that results in fibrosis of the bone marrow

• Presentation: anaemia and splenomegaly

• Diagnosis: bone marrow fibrosis, JAK-2 & tear drop RBC

• Management: chemotherapy when symptomatic

Outline

Background 

Commonest cause of splenomegaly in UK (with CLL)

Assessment

History:

• Drenching night sweats, 

• Weight loss > 10% over 6m

• Boney pains

Examination:

• Splenomegaly

• Fever > 37.5

Investigation

• Anaemia, Thrombocytosis 

• Tear drop RBCs on blood film

• JAK-2 positive

Diagnosis & Classification

Diagnostic criteria:  WHO 2016- Requires A1 & A2 and two B criteria

• A1: bone marrow fibrosis (3-4/4)

• A2: Jak-2 or MPL, or absence of BCR-ABL1/ reactive causes

• B criteria

  • • Palpable splenomegaly

    • Unexplained anaemia

    • Leuko-erythroblastosis

    • Tear drop red cells

    • Constitutional symptoms: drenching night sweats, weight loss > 10% over 6m, fever > 37.5,  boney pain

    • Histology: extramedullary hematopoiesis

Differential Diagnosis: CLL, Myelodysplasia

Classification

1. Primary 

2. Secondary to Polycythaemia vera or Essential thrombocytosis

Management

• Bone Marrow Stem Cell Transplant

• RBC transfusions

• Tyrosine kinase inhibitors (-tinib)

• Hydroxyurea

Med Reg Notes

Curative Treatment

This is only done by a successful bone marrow transplant. 

References and Resources

1. https://www.cancerresearchuk.org/about-cancer/myelofibrosis/what-is-myelofibrosis#:~:text=Myelofibrosis%20is%20a%20rare%20blood,cells%20can't%20develop%20properly.

2. https://mpnresearchfoundation.org/primary-myelofibrosis-pmf/

Page written in 2024.