Staging of Chronic Lymphocytic Leukemia
Staging helps to evaluate the severity of CLL. Based on the size, shape and other cellular morphological features, a specialist classifies the blood cells into specific type and subtype of leukemia.
The Rai system is commonly employed in the United States, while the Binet system is mainly used in Europe.
- Rai system. Using this system, doctors categorize chronic lymphocytic leukemia into five stages ranging from 0 to 4, with higher numbers indicating the advanced stages of disease. The stages are determined by the RBC and platelet counts and by the presence of an enlarged spleen, liver or lymph nodes.
- Binet system. Based on this system, chronic lymphocytic leukemia is classified into three stages from A to C, depending on the RBC and platelet counts, and by the number of affected lymphoid regions — such as the neck lymph nodes, groin lymph nodes, spleen and liver.
A summary of the Rai and the Binet system are presented in the table below:
|Stage||Clinical Features||Median Survival|
|Rai 0||Raised number of lymphocytes (in blood or marrow)||>10 years|
|1||As 0 + enlarged nodes||7 years|
|2||As 0 + enlarged spleen/liver, =/- enlarged nodes||7 years|
|3||As 0 + anemia, +/- enlarged nodes, liver or spleen||3-5 years|
|4||As 0 + low platelets, +/- anemia, enlarged nodes, liver or spleen||3-5 years|
|Binet A||Less than 3 areas of enlarged lymph nodes||>10 years|
|B||3 or more areas of enlarged lymph node||5 years|
|C||Anemia +/- low platelets||3-5 years|