National Blood Cancer Awareness Month

Myeloproliferative neoplasms (MY-ah-lo-pro-LIF-er-uh-tiv NEE-o-plaz-uhms), or MPNs, are a group of diseases in which a person’s bone marrow does not function properly. Bone marrow is a spongy tissue where blood cells are made, but in people with MPNs the wrong number of blood cells are made. This can cause a host of symptoms and complications.

MPNs are considered blood cancers. They are progressive conditions, meaning that they worsen over time. MPNs can affect people at any age, but they are more common in older adults. Mutations, or changes in certain genes, are thought to be major causes of what are known as Philadelphia chromosome-negative MPNs, or "classical" MPNs. But even people who do not have these mutations may have MPNs.

The 3 types of "classical" MPNs

• Myelofibrosis, or MF
• Polycythemia vera, or PV
• Essential thrombocythemia, or ET

Polycythaemia vera (PV), in which too many red blood cells are made; essential thrombocythaemia (ET) in which too many platelets are made and myelofibrosis.

Myelofibrosis is caused by an abnormality in the cells that make platelets, which clot the blood and form scars. The body’s feedback system, which tells the bone marrow to make more blood cells, is disrupted. As the disease develops, the tissue in the bone marrow scars over and becomes useless. Blood cell production is then taken over by the liver and spleen. These organs are not able to make enough blood cells, and so people with myelofibrosis have a low blood count, with too few blood cells.