Hairy Cell Leukemia
(HCL; Leukemic Reticuloendotheliosis)
by Rick Alan
Hairy cell leukemia (HCL) is a rare form of cancer. It involves white blood cells called B lymphocytes. White blood cells protect the body from infection. HCL gets its name from the tiny hair-like projections that stick out of the surface of these cancer cells. Illness results from the build up of these cancer cells in the bone marrow and spleen.
HCL usually develops slowly over time. Early on, there may not be any symptoms. The cancer cells eventually overgrow the bone marrow. This affects the growth of normal cells such as red blood cells and platelets.
Symptoms may include:
You will be asked about your symptoms and medical history. A physical exam will be done.
Your bodily fluids and tissues may be tested. This can be done with:
Images may be taken of your bodily structures. This can be done with a CT scan.
HCL is a slow-growing cancer. As HCL progresses, treatment may include:
American Cancer Society
The Leukemia & Lymphoma Society
BC Cancer Agency
Canadian Cancer Society
General information about hairy cell leukemia. National Cancer Institute website. Available at:
Hairy cell leukemia. EBSCO DynaMed website. Available at:
Hairy cell leukemia. The Leukemia & Lymphoma Society website. Available at:
Last reviewed November 2013 by Mohei Abouzied, MD