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.
Plasma cell leukemia (PCL) is an aggressive form of multiple myeloma characterized by high levels of abnormal plasma cells circulating in the peripheral (circulating) blood. Normal plasma cells in the bone marrow produce antibodies that fight infection. In myeloma most of the abnormal plasma cells remain in the bone marrow and are not found in the peripheral blood. In PCL, the abnormal plasma cells are in the peripheral blood. Therefore, PCL is considered to be an advanced form of myeloma.