Myelofibrosis (MF) is a chronic form of blood cancer where scar tissue in the bone marrow slows down the production of healthy blood cells. A shortage of blood cells causes many of the symptoms and complications of MF, such as fatigue, easy bruising, fever, and bone or joint pain.

Many people don’t experience any symptoms in the early stages of the disease. As the disease progresses, symptoms and complications tied to abnormal blood cell counts may begin to appear.

It’s important to work with your doctor to proactively treat MF, especially as soon as you begin experiencing symptoms. Treatment can help reduce your risk of complications and increase survival.

Here’s a closer look at the potential complications of MF and how you can reduce your risk.

Your spleen helps fight off infections and filters out old or damaged blood cells. It also stores red blood cells and platelets that help your blood clot.

When you have MF, your bone marrow can’t make enough blood cells due to scarring. Blood cells are eventually produced outside the bone marrow in other parts of your body, such as your spleen.

This is referred to as extramedullary hematopoiesis. The spleen sometimes becomes abnormally large as it works harder to make these cells.

An enlarged spleen (splenomegaly) can cause uncomfortable symptoms. It can cause abdominal pain when it pushes up against other organs and make you feel full even when you haven’t eaten much.

When blood cells are produced outside the bone marrow, noncancerous tumors of developing blood cells sometimes form in other areas of the body.

These tumors may cause bleeding inside your gastrointestinal system. This may make you cough or spit up blood. Tumors may also compress your spinal cord or cause seizures.

Blood flows from the spleen to the liver through the portal vein. Increased blood flow to an enlarged spleen in MF causes high blood pressure in the portal vein.

An increase in blood pressure sometimes forces excess blood into the stomach and esophagus. This may rupture smaller veins and cause bleeding. About 7 percent of people with MF experience this complication.

Platelets in the blood help your blood to clot after an injury. Platelet count can fall below normal as MF progresses. A low number of platelets is known as thrombocytopenia.

Without enough platelets, your blood can’t clot properly. This can make you bleed more easily.

MF can harden your bone marrow. It can also lead to inflammation in the connective tissues around the bones. This leads to bone and joint pain.

MF causes the body to produce more uric acid than normal. If the uric acid crystallizes, it sometimes settles in the joints. This is referred to as gout. Gout can cause swollen and painful joints.

A low red blood cell count known as anemia is a common MF symptom. Sometimes anemia becomes severe and causes debilitating fatigue, bruising, and other symptoms.

For about 15 to 20 percent of people, MF progresses to a more severe form of cancer known as acute myeloid leukemia (AML). AML is a rapidly progressing cancer of the blood and bone marrow.

Your doctor may prescribe various treatments to address MF complications. These include:

  • JAK inhibitors, including ruxolitinib (Jakafi) and fedratinib (Inrebic)
  • immunomodulatory drugs, such as thalidomide (Thalomid), lenalidomide (Revlimid), interferons, and pomalidomide (Pomalyst)
  • corticosteroids, such as prednisone
  • surgical removal of the spleen (splenectomy)
  • androgen therapy
  • chemotherapy drugs, such as hydroxyurea

It’s essential to work with your doctor to manage MF. Frequent monitoring is key to reducing your risk of MF complications. Your doctor may request that you come in for blood counts and physical exams once or twice per year or as often as once a week.

If you currently have no symptoms and low-risk MF, there’s no evidence that you’ll benefit from earlier interventions. Your doctor may wait to begin treatments until your condition progresses.

If you have symptoms or intermediate- or high-risk MF, your doctor may prescribe treatments.

The JAK inhibitors ruxolitinib and fedratinib target abnormal pathway signaling caused by a common MF gene mutation. These drugs have been shown to significantly reduce spleen size and address other debilitating symptoms including bone and joint pain. Research suggests they may greatly reduce the risk of complications and increase survival.

A bone marrow transplant is the only treatment that can potentially cure MF. It involves receiving an infusion of stem cells from a healthy donor, which replace faulty stem cells causing MF symptoms.

This procedure carries significant and potentially life threatening risks. It’s usually only recommended for younger people without other preexisting health conditions.

New MF treatments are constantly being developed. Try to stay up to date on the latest research in MF, and ask your doctor about whether you should consider enrolling in a clinical trial.

Myelofibrosis is a rare cancer where scarring keeps your bone marrow from producing enough healthy blood cells. If you have intermediate- or high-risk MF, several treatments can address symptoms, reduce your risk of complications, and potentially increase survival.

Many ongoing trials continue to explore new treatments. Stay in touch with your doctor and discuss which treatments may be appropriate for you.