In chronic lymphocytic leukemia (CLL), the leukemia cells may spread from the blood and bone marrow to other parts of the body, such as the lymph nodes, liver, and spleen. It is important to know whether these cells have spread in order to provide the patient with the best leukemia treatment options.
The most commonly used staging and classification systems used by doctors to describe CLL are the Rai system and the Binet System.
Rai System for Staging CLL
The Rai system is based on lymphocytosis, an increase in the number or proportion of lymphocytes (a type of white blood cell) in the blood that isn’t linked to any other cause, such as an infection.
In this staging system, chronic lymphocytic leukemia is divided into five different stages:
Stage 0: The patient has lymphocytosis with more than 5000 lymphocytes per microliter of blood but no other physical signs.
Stage I: The patient has lymphocytosis and enlarged lymph nodes. The patient does not have an enlarged liver or spleen, anemia, or low levels of platelets.
Stage II: The patient has lymphocytosis and an enlarged spleen and/or liver and may or may not have swollen lymph nodes.
Stage III: The patient has lymphocytosis and anemia. The patient may or may not have swollen lymph nodes and an enlarged liver or spleen.
Stage IV: The patient has lymphocytosis and low levels of platelets. The patient may or may not have swollen lymph nodes, an enlarged liver or spleen, or anemia.
Sometimes, doctors break these stages into “risk groups” that help them determine when to begin treatment:
- Low risk: Stage 0
- Intermediate risk: Stages I and II
- High risk: Stages III and IV
Binet staging system for CLL
This staging system classifies CLL by the number of affected lymphoid tissue groups (neck lymph nodes, underarm lymph nodes, groin lymph nodes, spleen, and liver) and by whether or not the patient has anemia (too few red blood cells) or thrombocytopenia (too few blood platelets). There are three stages: A, B, and C.
Stage A: The patient does not have anemia or low levels of platelets. Leukemia can be felt in fewer than three areas of lymph nodes (Rai stages 0, I, and II).
Stage B: The patient does not have anemia or low levels of platelets. The leukemia is in three or more areas of lymph nodes (Rai stages I and II).
Stage C: The patient has anemia and/or low levels of platelets (thrombocytopenia). Leukemia is in any number of lymph nodes (Rai stages III and IV).
