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Primary myelofibrosis (PMF) is a rare type of blood cancer belonging to the group of myeloproliferative neoplasms (MPNs). In this condition, normal bone marrow tissue is gradually replaced by fibrous (scar) tissue. This scarring impairs the bone marrow’s ability to produce healthy blood cells (red blood cells, white blood cells, and platelets), leading to low blood cell counts. As a result, blood cell production shifts to other organs, such as the spleen and liver, which subsequently enlarge.
Common symptoms include severe fatigue, enlargement of the spleen (which may cause pain or a feeling of fullness in the left side of the abdomen), weight loss, night sweats, fever, and bone pain.
Statistics: PMF is a rare disease most often diagnosed in people over the age of 60. The median age at diagnosis is approximately 65 years.
Heredity: Primary myelofibrosis is generally not considered an inherited disease. It is caused by acquired genetic mutations (such as in the JAK2, CALR, or MPL genes) that develop during a person’s lifetime and are not passed on to future generations.
