Abstract
This chapter includes answers to practice‐based questions covering the new principles of diagnosis, treatment, and outcomes in Primary Myelofibrosis (PMF). PMF is a clonal hematologic malignancy clinically characterized by splenomegaly, constitutional symptoms, cytopenias, and evolution to acute myeloid leukemia. Myeloproliferative neoplasms (MPNs) share morphological, pathological, molecular, and clinical features and frequently evolve from one clinical phenotype to another. In order to determine the diagnosis of PMF, it is necessary to exclude other MPNs, in particular chronic myeloid leukemia. At time of bone marrow biopsy, it is important to also obtain cytogenetic analysis and driver mutational testing, for both diagnostic and prognostic purposes. Autoimmune myelofibrosis closely resembles PMF in bone marrow morphology but is often associated with lymphocytic infiltration. The bromodomain and extra terminal domain (BET) family of proteins regulate gene transcription of several pro‐fibrotic cytokines, and BET inhibitor has shown preclinical activity in PMF.