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Stages of Chronic Myelogenous Leukemia

After chronic myelogenous leukemia has been diagnosed, tests are done to find out if the cancer has spread.

The extent or spread of cancer is usually described as stages. In chronic myelogenous leukemia (CML), the disease is classified by phase: chronic phase, accelerated phase, or blastic phase. It is important to know the phase in order to plan treatment. The information from tests and procedures done to diagnose chronic myelogenous leukemia is also used to plan treatment.

Chronic myelogenous leukemia has 3 phases.

As the amount of blast cells increases in the blood and bone marrow, there is less room for healthy white blood cells, red blood cells, and platelets. This may result in infections, anemia, and easy bleeding, as well as bone pain and pain or a feeling of fullness below the ribs on the left side. The number of blast cells in the blood and bone marrow and the severity of signs or symptoms determine the phase of the disease.

Chronic phase

In chronic phase CML, fewer than 10% of the cells in the blood and bone marrow are blast cells.

Accelerated phase

In accelerated phase CML, 10% to 19% of the cells in the blood and bone marrow are blast cells.

Blastic phase

In blastic phase CML, 20% or more of the cells in the blood or bone marrow are blast cells. When tiredness, fever, and an enlarged spleen occur during the blastic phase, it is called blast crisis.

Chronic myelogenous leukemia can relapse (return) after it has been treated.

In relapsed CML, the number of blast cells increases after a remission.

This information is not intended to replace the advice of a doctor. Navigating Care disclaims any liability for the decisions you make based on this information. This information was sourced and adapted from Adapted from the National Cancer Institute's Physician Data Query (PDQ®) Cancer Information Summaries on www.cancer.gov.