Making an educated treatment decision begins with the stage, or progression, of the disease. The stage of leukemia is one of the most important factors in evaluating treatment options.
Most cancers are staged based on the size and spread of tumors. However, because leukemia already occurs in the developing blood cells within the bone marrow, leukemia staging is a little bit different. The stages of leukemia are often characterized by blood cell counts and the accumulation of leukemia cells in other organs, like the liver or spleen.
Leukemia stages vary based on disease type. And, some of the leukemias may be broken out into subtypes during the staging process.
The acute types of leukemia (AML and ALL), are sometimes staged based on the type of cell involved and how the cells look under a microscope. This is called the French-American-British (FAB) classification system.
Lymphocytic leukemias (CLL and ALL) occur in a type of white blood cell called lymphocytes. The white blood cell count at the time of diagnosis may be used to help stage the leukemia. Likewise, staging for myeloid leukemias (CML and AML) is based on the number of myeloblasts (immature white blood cells) found in the blood or bone marrow.
Factors affecting leukemia staging and prognosis
- White blood cell or platelet count
- Age (advanced age may negatively affect prognosis)
- History of prior blood disorders
- Chromosome mutations or abnormalities
- Bone damage
- Enlarged liver or spleen