Chronic lymphocytic leukemia (CLL) shares some similar features and symptoms with other closely related types of leukemia. They all have one thing in common: They begin in a lymphocyte that becomes cancerous and accumulates in the blood, bone marrow or spleen.
The diseases represent a range of clinical severity. At one end of the range, there are the diseases that may be stable and may not advance in severity for some months or years, or occasionally indefinitely. At the other end of the range, there are diseases associated with difficulties that may be present at diagnosis and possibly get worse, requiring immediate treatment and frequent observation.
Less rapidly progressive
More rapidly progressive
- Prolymphocytic leukemia. This disease can be a B-cell or a T-cell type and features large numbers of lymphocytes in the blood. These lymphocytes are a mixture of small lymphocytes akin to CLL cells and large, more immature-appearing lymphocytes akin to acute lymphoblastic leukemia cells. In general, prolymphocytic leukemia develops more rapidly than the chronic form of lymphocytic leukemia, but more slowly than the acute form. It is treated with the same drugs that are used for other types of lymphocytic leukemia. In addition, there are a number of clinical trials to study new treatment approaches for prolymphocytic leukemia.