Diagnosis guide
Myelofibrosis
Myelofibrosis is a rare blood cancer in which abnormal blood cells and scar-like fibers build up inside the bone marrow, so the marrow makes blood less well. It is one of the myeloproliferative neoplasms (MPNs). Its name depends on how it started: primary myelofibrosis begins on its own, while post-polycythemia vera and post-essential thrombocythemia myelofibrosis develop from those earlier MPNs. Medicines called JAK inhibitors can shrink an enlarged spleen and ease symptoms. A donor stem cell transplant is the only treatment that may cure it, and it is considered for selected people, usually those with higher-risk disease.
In short
- Myelofibrosis is a rare blood cancer in which scar-like fibers build up in the bone marrow, so blood-making can shift to the spleen and liver.
- It can start on its own, as primary myelofibrosis, or develop from polycythemia vera or essential thrombocythemia, and treatment depends on risk and symptoms.
- JAK inhibitors can shrink the spleen and ease symptoms, while a donor stem cell transplant is the only treatment that may cure it, for selected people.
Find the subtype on your report
The exact diagnosis shapes the treatment options. Your care team can explain the name on your report.
Primary myelofibrosis (PMF)
Primary myelofibrosis is a blood-forming stem cell cancer that disrupts marrow function and can cause marrow scarring. Blood production may shift to the spleen and liver, leading to enlarged organs and symptoms.
Donor transplant optionPost-polycythemia vera myelofibrosis (post-PV MF)
Post-polycythemia vera myelofibrosis is progression of previously established polycythemia vera (PV) to a fibrotic marrow disorder. Blood production and symptoms change; anemia and an enlarged spleen may develop after the earlier phase of excess red cells.
Donor transplant optionPost-essential thrombocythemia myelofibrosis (post-ET MF)
Post-essential thrombocythemia myelofibrosis is progression of a previously established essential thrombocythemia (ET) to a fibrotic marrow disorder. Anemia, an enlarged spleen and other changes can replace the earlier pattern of mainly raised platelets.
Donor transplant option
Support for patients and families
These independent organizations offer information and support. JBF is not affiliated with them.
- MPN Research Foundation A nonprofit that funds MPN research and offers patients and caregivers resources, help finding support groups, clinical trial information and personal stories.United States
- MPN Voice A UK charity offering clear information, a buddy program, patient forums and emotional support to people with MPNs and their families.United Kingdom
- MPN Advocacy & Education International A nonprofit running education programs, support groups and advocacy for people with myelofibrosis, polycythemia vera and essential thrombocythemia, in the US and abroad.United States and international
Someone may be waiting for a match.
Some people with myelofibrosis are treated with a transplant from a donor. When no relative matches, that donor is often a stranger who joined a registry.
Join the registry
JBF points you to the official registry that serves your country. It explains who can join and what donation involves.
Help a family run a drive
If someone you love needs a donor, a registration drive can add many potential donors at once, for them and for others.
Support this work
Gifts to the Jada Bascom Foundation support donor-awareness education like this guide, community outreach, drive planning and referrals to official registries.
Sources and further reading
- Myeloproliferative Neoplasms Treatment (PDQ), Patient Version
National Cancer Institute, 2025-05-12 - Myeloproliferative Neoplasms Treatment (PDQ), Health Professional Version
National Cancer Institute, 2024-09-27
