Classic hairy cell leukemia

Classic hair cell leukemia is a rare form of leukemia. It is based on abnormal B lymphocytes in the spleen, bone marrow and peripheral blood. The name refers to the abnormal form of lymphocytes having hair-like extensions.

HCL is a slowly progressive leukemia and accounts for only about 2% of all leukemia cases. Men are more often affected than women, and the mean age of onset is 55 years.

Most of the clinical symptoms result from impaired blood cell production causing anemia, susceptibility to infections, fatigue, and an increased bleeding tendency. Almost all patients also experience hepatosplenomegaly and symptoms associated to it (e.g. abdominal pain, liver function abnormalities).