Learn about the three most important lines of latitude on Earth - the equator, Tropic of Cancer, and Tropic of Capricorn. Learn about the three most important lines of latitude on Earth - the equator, Tropic of Cancer, and Tropic of Capricorn.
General Discussion. Hairy cell leukemia (HCL) is a rare type of blood cancer characterized by abnormal changes in white blood cells known as B lymphocytes. The bone marrow creates too many of these defective cells, known as hairy cells because of the thin hair-like projections found on their surface.
Hairy cell leukemia. Hairy cell leukemia cells, which appear as the darker cells in this photo, are surrounded by a halo of fine projections (villi). To diagnose hairy cell leukemia, your doctor may take a sample of bone marrow from your body and examine it under a microscope to look for hairy cells.