MF Diagnosis and Prognosis

These tools are designed to help evaluate a patient for myelofibrosis (MF). For patients who have been diagnosed with MF, the tools can help estimate prognosis based on validated models.

Use the WHO Criteria for Diagnosis of Primary Myelofibrosis (PMF)

This tool helps evaluate whether a patient’s profile is consistent with a diagnosis of PMF based on World Health Organization (WHO) criteria. Diagnosis requires meeting all 3 major criteria and at least 1 minor criterion (confirmed in 2 consecutive determinations).1

Check the criteria corresponding to the patient’s clinical presentation.


Proliferation and atypia of megakaryocytes accompanied by either reticulin and/or collagen fibrosis grades 2 or 3 on a scale of 0 to 3 

Not meeting WHO criteria for ET, PV, BCR-ABL1+ CML, myelodysplastic syndromes, or other myeloid neoplasms

Presence of JAK2, CALR, or MPL mutation or in the absence of these mutations, presence of another clonal markera or absence of reactive myelofibrosisb


Anemia not attributed to a comorbid condition
Leukocytosis ≥11 × 109/L
Palpable splenomegaly
LDH increased to above upper normal limit of institutional reference range
CALR, calreticulin; CML, chronic myelogenous leukemia; JAK, Janus-associated kinase; LDH, lactate dehydrogenase; MPL, myeloproliferative leukemia virus oncogene. aIn the absence of any of the 3 major clonal mutations, the search for the most frequent accompanying mutations (eg, ASXL1, EZH2, TET2, IDH1/IDH2, SRSF2, SF3B1) is of help in determining the clonal nature of the disease. bBone marrow fibrosis secondary to infection, autoimmune disorder or other chronic inflammatory conditions, hairy cell leukemia or other lymphoid neoplasm, metastatic malignancy, or toxic (chronic) myelopathies.

1. Arber DA, Orazi A, Hasserjian R, et al. Blood. 2016;127(20):2391-2405.