Limber

MF is a rare, chronic blood cancer. It can "progress," or get worse, over time. For example, new symptoms may appear or existing symptoms may get worse.1 MF is part of a group of diseases called "myeloproliferative neoplasms," or MPNs. Healthcare professionals sometimes call this condition a bone marrow cancer or blood cancer. Bone marrow is a spongy tissue inside of the bone, and is the primary place where blood cells are made. People with MF have a defect in their bone marrow that results in an abnormal production of blood cells, causing scar tissue to form. 2 MF can result from a progression of other bone marrow diseases or it can occur on its own.3

MF can cause the spleen to become quite large. The spleen is a crescent shaped organ that is normally located just under rib cage on the left side. With MF, the spleen can extend below your rib cage, sometimes as much as 8 to 10 inches (20 to 25 cm). Symptoms of an enlarged spleen can include pain or discomfort in the abdomen or under the left ribs, and feeling full when you have not eaten or have eaten very little.4,5,6 In addition to the symptoms caused by an enlarged spleen, MF can affect the body in other ways, including fatigue, itching, night sweats, fever, unexplained weight loss, bone pain, and bruising or bleeding easily.7,8,9

MF is complex and may have many contributing factors. Scientists think that it may be related to changes in certain genes. These changes are called "mutations."7 People with MF have bone marrow that does not work correctly. In some people with this condition, mutations may affect the behavior of certain proteins, and cause the bone marrow to make too many or too few blood cells. This imbalance of blood cells may cause some of the symptoms of MF.7 This often happens even if mutations are not present.10 Another cause of symptoms may be the overproduction of certain proteins called "cytokines." Cytokines can cause inflammation. When your body has too many cytokines, you may experience itching, night sweats, and some other symptoms of MF.7,8,10