Chronic lymphocytic leukemia (CLL) is the only type of leukemia with well-defined stages.
In that way, it is staged similarly to cancer of organs, such as breast or lung. The Rai system is the classification system used in the United States. It classifies leukemia into stages 0 through IV. Another system, called the Binet system, classifies leukemia into stages A through C. It is used in some parts of Europe.
Stage 0. In this stage, your blood has too many lymphocytes, called lymphocytosis. You don't have any other signs or symptoms of leukemia. This stage is considered low risk, which means people tend to have longer survival rates and generally have no or few symptoms.
Stage I. In this stage, your blood has too many lymphocytes, called lymphocytosis, and your lymph nodes are larger than normal. This stage is considered intermediate risk.
Stage II. In this stage, your blood has too many lymphocytes, called lymphocytosis, and your liver may be swollen, called hepatomegaly. Or your spleen may be swollen, called splenomegaly. Or they may both be swollen. Your lymph nodes may also be larger than normal. This stage is also considered intermediate risk.
Stage III. In this stage, your blood has too many lymphocytes, called lymphocytosis, and you have too few red blood cells, called anemia. Your lymph nodes, liver, or spleen may also be larger than normal. This stage is considered high risk.
Stage IV. In this stage, your blood has too many lymphocytes and too few platelets, called thrombocytopenia. Your lymph nodes, liver, or spleen may be larger than normal, and you may have too few red blood cells. This stage is considered high risk.
In addition to the stage of your CLL, other factors help predict your outlook for survival. Your doctor may take these factors into account when evaluating your treatment options. Adverse prognostic factors, such as older age, male gender, and high blood levels of beta-2 microglobulin, tend to be linked to a shorter survival. Favorable prognostic factors tend to predict a longer survival.
Among other factors, CLL cells that have developed the ability to make antibodies tend to be associated with a more favorable prognosis with an average survival of 15 years or more. If the CLL cells do not mature and create antibodies, the survival time tends to be shorter, an average of about 8 years. Doctors can tell the difference between these 2 groups with lab tests that look for substances called ZAP-70 and CD38 on the leukemia cells.