For most cancers, staging is the process of determining how much a cancer has spread. Identifying the stage can often be useful because it can help guide treatment and determine a person’s prognosis (outlook). Most types of cancer are staged based on the size of the tumor and how far the cancer has spread.
Chronic lymphocytic leukemia (CLL) does not typically form tumors as it is present in the bone marrow and blood. In many cases, by the time it is discovered, it has also spread to other organs such as the spleen, liver, and lymph nodes. Because of this, the outlook for a person with CLL may depend on other information, such as all the lab test results and the results of imaging tests, such as CT Scans or MRIs. However RAI staging is based simply on the blood tests and physical exam. Imaging at the time of diagnosis is most often not necessary.
In the USA, the most commonly used clinical staging system for chronic lymphocytic leukemia (CLL) is the Rai staging system developed by Dr. Kanti Rai in 1975 and is still useful today. The original article from Blood can be found here.
It divides CLL into 5 stages:
|Rai stage 0:||Lymphocytosis (high blood count of lymphocytes) and no enlargement of the lymph nodes, spleen, or liver, and with near normal red blood cell and platelet counts.|
|Rai stage I:||Lymphocytosis plus enlarged lymph nodes. The spleen and liver are not enlarged and the red blood cell and platelet counts are normal or only slightly low.|
|Rai stage II:||Lymphocytosis plus an enlarged spleen (and possibly an enlarged liver), with or without enlarged lymph nodes. The red blood cell and platelet counts are normal or only slightly low|
|Rai stage III:||Lymphocytosis plus anemia (too few red blood cells), with or without enlarged lymph nodes, spleen, or liver. Platelet counts are near normal.|
|Rai stage IV:||Lymphocytosis plus thrombocytopenia (too few platelets), with or without anemia, enlarged lymph nodes, spleen, or liver.|
The Rai stages are divided into low, intermediate, and high-risk. It helps determine best management when used with other newer prognostic factors.
Stage 0 is low-risk.
Stages I and II are intermediate-risk.
Stages III and IV are high-risk.
Brian Koffman, MD 2/1/16
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