Hairy cell leukemia is a rare, slow-growing cancer of the blood in which your bone marrow makes too many B cells (lymphocytes), a type of white blood cell that fights infection. These excess B cells are abnormal and look "hairy" under a microscope.
Common symptoms of HCL includes persistently feeling tired, weakness, weight loss for no reason, shortness of breath, excessive sweating (most often at night), swollen lymph nodes, frequent infections and fevers, small red spots on the skin. The main treatment for hairy cell leukemia is chemotherapy, purine analog drugs either cladribine (2-CdA) or pentostatin, monoclonal antibody rituximab, surgery or interferon alpha.
Approximately 25% present with infection and 70% have either documented or suspected infection during the course of the disease. It has been reported in up to 60% of survival rate during therapy. Most patients with hairy cell leukemia can expect to live 10 years or longer after diagnosis and treatment.