Chronic Myeloproliferative Neoplasms

Chronic myeloproliferative neoplasms are a group of slow-growing blood cancers. These conditions cause your bone marrow to make too many blood cells. The bone marrow is the soft tissue inside your bones where blood cells are made.

The main types include polycythemia vera, essential thrombocythemia, and primary myelofibrosis. Polycythemia vera causes too many red blood cells. Essential thrombocythemia makes too many platelets. Primary myelofibrosis leads to scarring in the bone marrow. These conditions develop slowly over months or years.

Many people with these conditions have a genetic change called the JAK2 V617F mutation. This mutation causes cells to grow and divide when they should not. The mutation is acquired during your lifetime, not inherited from your parents. Understanding your genetic profile helps doctors choose the right treatment approach.

• Fatigue and weakness that does not improve with rest
• Headaches or dizziness
• Night sweats that soak your clothes or sheets
• Unexplained weight loss over several months
• Feeling full quickly when eating
• Pain or fullness below the ribs on the left side
• Itching, especially after a warm bath or shower
• Unusual bleeding or bruising
• Numbness or tingling in your hands or feet
• Vision problems or blurred vision

Many people have no symptoms in the early stages. The condition is often found during routine blood work. Some people live for years without knowing they have it.

Most chronic myeloproliferative neoplasms are caused by genetic mutations in bone marrow cells. The JAK2 V617F mutation is found in about 95% of people with polycythemia vera. It is also present in about half of those with essential thrombocythemia or primary myelofibrosis. Other mutations like CALR and MPL can also cause these conditions. These mutations make cells grow out of control.

The exact cause of these mutations is unknown in most cases. Age is the biggest risk factor, with most people diagnosed after age 60. Men and women are affected equally. Exposure to high levels of radiation or certain chemicals may increase risk. Family history plays a small role, but most cases are not inherited.

Diagnosis starts with a complete blood count, which measures red blood cells, white blood cells, and platelets. Abnormal counts may suggest a myeloproliferative neoplasm. Your doctor will also check for an enlarged spleen through a physical exam.

Genetic testing is essential for confirming the diagnosis. The JAK2 V617F mutation analysis looks for the specific genetic change that drives most cases. A bone marrow biopsy may also be needed to examine cells under a microscope. Talk to your doctor about specialized testing and evaluation by a blood cancer specialist called a hematologist.

• Regular monitoring with blood tests to track disease progression
• Phlebotomy, a procedure that removes excess blood to reduce red blood cell counts
• Low-dose aspirin to prevent blood clots
• Hydroxyurea or other medications to reduce blood cell production
• JAK inhibitors like ruxolitinib that target the genetic mutation
• Medications to reduce enlarged spleen size and related symptoms
• Staying hydrated and avoiding extreme temperatures
• Managing cardiovascular risk factors like high blood pressure and cholesterol
• Regular follow-up with a hematologist for ongoing care