Longevity & AgingNew German guideline reshapes how doctors diagnose and treat primary myelofibrosis
Myelofibrosis is a rare blood cancer in which abnormal stem cells drive bone marrow scarring, largely through overactive JAK2 signaling. This 2025 German ONKOPEDIA guideline summarizes current diagnosis, risk assessment, and treatment. It reflects the 2022 WHO and ICC criteria, which recognize prefibrotic primary myelofibrosis as a distinct entity. Prognosis depends on age, symptoms, blood counts, and increasingly on cytogenetic and molecular markers. Allogeneic stem cell transplantation is the only potentially curative option, generally for transplant-eligible patients at high or very-high risk by MIPSS70+ v2.0. For symptoms, ruxolitinib remains the standard, with fedratinib and momelotinib as additional JAK inhibitors. Momelotinib appears especially useful for patients with moderate to severe anemia. Newer drugs and combinations show promise but are not yet available for routine care.