Stages of chronic lymphocytic leukemia (CLL)

Staging describes or classifies a cancer based on how much cancer there is in the body and where it is when first diagnosed. This is often called the extent of cancer. Information from tests is used to find out the size of the tumour, which parts of the organ have cancer, whether the cancer has spread from where it first started and where the cancer has spread. Your healthcare team uses the stage to plan treatment and estimate the outcome (your prognosis).

Staging of blood cancers like chronic lymphocytic leukemia (CLL) is different from that of other cancers because CLL does not form a solid tumour. CLL is a cancer of the cells in the blood and bone marrow, where new blood cells are formed. The stage of the disease is based on blood cell counts and if the cancer has spread to the lymph nodes, spleen or liver.

The 2 staging systems for CLL are the Rai staging system and the Binet staging system. Sometimes doctors talk about a risk group for CLL. The risk group describes how likely the CLL is to worsen and need treatment. If the CLL worsens, doctors will do more tests to see if the CLL has reached a new stage.

The most common staging system for CLL is the Rai staging system. For CLL there are 5 stages – stage 0 followed by stages 1 to 4. Often the stages 1 to 4 are written as the Roman numerals I, II, III and IV. The stages are based on the numbers of lymphocytes, red blood cells and platelets and whether the lymph nodes, spleen or liver are larger than normal. Generally, the higher the stage number, the more advanced the cancer. Talk to your doctor if you have questions about staging.

The lymphocyte counts in the blood (called lymphocytosis) are higher than normal.

The numbers of red blood cells and platelets are normal.

The lymph nodes, spleen and liver are not enlarged.

Stage 0 CLL is low risk. This means it may take a very long time to get worse.

The lymphocyte counts in the blood are higher than normal.

The numbers of red blood cells and platelets are normal.

Some lymph nodes are enlarged, but the spleen and liver are not enlarged.

Stage 1 CLL is intermediate risk. This means there is a moderate chance that it will get worse.

The lymphocyte counts in the blood are higher than normal.

The numbers of red blood cells and platelets are normal.

The spleen is enlarged and some lymph nodes and the liver may also be enlarged.

Stage 2 CLL is intermediate risk.

The lymphocyte counts are higher than normal, and the number of red blood cells (called anemia) in the blood is lower than normal.

The number of platelets is normal.

The lymph nodes, spleen or liver may be enlarged.

Stage 3 CLL is high risk. This means that it is likely to get worse.

The lymphocyte counts are higher than normal, and the number of platelets (called thrombocytopenia) in the blood is lower than normal.

The number of red blood cells may be low.

The lymph nodes, spleen or liver may be enlarged.

Stage 4 CLL is high risk.

The Binet staging system has 3 stages – A, B and C. The stages are based on the numbers of red blood cells and platelets in the blood and the number of areas of lymphatic tissue that are enlarged. The areas of lymphatic tissue include the spleen, liver and lymph nodes in the neck, underarm areas and groin.

The lymphocyte counts are higher than normal.

The numbers of red blood cells and platelets are normal.

Fewer than 3 areas of lymphatic tissue are enlarged.

Stage A CLL is low risk.

The lymphocyte counts are higher than normal.

The numbers of red blood cells and platelets are normal.

Three or more lymphatic tissue areas are enlarged.

Stage B CLL is intermediate risk.

The lymphocyte counts are higher than normal.

The numbers of red blood cells or platelets or both are low.

Any number of lymphatic tissue areas are enlarged.

Stage C CLL is high risk.

Relapsed, or recurrent, CLL means the leukemia has come back after treatment and reaching remission. Remission is usually defined as a decrease in or the disappearance of signs and symptoms and improved blood cell counts. If the CLL relapses, doctors may stage it again. This is called re-staging.

Refractory disease means the leukemia did not respond to treatment.