Myelofibrosis (MF) is a rare blood cancer where dysregulation of the JAK-STAT pathway drives the proliferation of abnormal blood stem cells, local inflammation and fibrosis in the bone marrow. These changes compromise marrow function and lead to a chronic inflammatory state, driving the three hallmarks of MF:

  1. progressive anemia, often in association with thrombocytopenia or other cytopenias.
  2. constitutional symptoms such as fatigue, night sweats, fever, bone pain and pruritus.
  3. enlargement of the spleen (splenomegaly), which can be associated with abdominal distension, pain and early satiety.

The median survival for all patients with MF is about 6 years but it is considerably worse for high-risk patients at just 2.25 years, respectively. Transfusion dependency and moderate to severe anemia are critical negative prognostic factors in MF and inversely correlated with quality of life.