Myeloproliferative Neoplasms

Myeloproliferative neoplasms (MPNs) are a group of rare blood cancers that originate in the bone marrow, where red blood cells, white blood cells and platelets are produced. MPNs occur when the bone marrow overproduces one or more types of blood cells, which can also lead to complications related to bleeding and blood clotting. Though uncommon, MPN cancer can potentially progress into a more serious condition, such as acute leukemia.

What causes myeloproliferative neoplasms?

MPNs result from harmful changes in the stem cells of the bone marrow. The most common mutation involves the JAK2 gene, which produces a protein that helps control blood cell production. Other mutations associated with MPN cancer involve the CALR and MPL protein-coding genes. In general, these gene mutations disrupt normal cell regulation, causing uncontrolled cell growth and the development of MPNs. The exact triggers of these genetic changes are not yet fully understood.

What are the risk factors for myeloproliferative neoplasms?

Known risk factors for MPNs include:

• Advanced age (most cases are diagnosed after age 60)
• Certain genetic predispositions, such as inherited gene mutations or family history of blood disorders
• Exposure to high levels of radiation or certain chemicals

In many cases, however, no specific hereditary or environmental risk factor is identified.

What are the signs and symptoms of myeloproliferative neoplasms?

Early-stage MPNs do not always have noticeable symptoms and are often detected during routine blood testing. As MPN cancer advances, it may cause:

• Weakness and fatigue
• Unexplained weight loss
• Spleen enlargement (splenomegaly)
• Abdominal fullness
• Easy bleeding and bruising
• Frequent infections
• Night sweats
• Headaches
• Bone pain

How are myeloproliferative neoplasms diagnosed?

MPNs are usually diagnosed through a combination of blood and bone marrow testing. Blood work may reveal abnormal levels of red blood cells, white blood cells or platelets, along with other irregularities in blood composition. Genetic testing may also be performed to check for certain gene mutations, such as JAK2, CALR and MPL gene mutations, which are known to be associated with MPN cancer. Finally, a bone marrow biopsy, which involves the microscopic examination of a sample of bone marrow cells by a pathologist, is typically necessary to confirm the diagnosis.

How are myeloproliferative neoplasms treated?

MPN treatment can vary based on the specific type of cancer, the severity of symptoms and the patient’s overall health. Common options include:

• Phlebotomy – Blood may be periodically drawn to reduce red blood cell levels and help prevent MPN complications.
• Medications – Drugs such as hydroxyurea or interferon may be used to reduce the production of abnormal blood cells and control related symptoms, such as anemia and spleen enlargement.
• Targeted therapy – JAK inhibitors such as ruxolitinib can target certain genetic mutations associated with MPNs.
• Blood thinners – Blood clots are a common complication of MPNs.
• Bone marrow transplantation – In severe cases, a transplant may be considered to replace abnormal bone marrow with healthy cells.

Benefit from world-class care at Moffitt Cancer Center

If you would like to learn more about myeloproliferative neoplasms, you can request an appointment with a specialist in the Blood and Marrow Transplant and Cellular Immunotherapy Program at Moffitt by calling 1-888-663-3488 or submitting a new patient registration form online. We do not require referrals.