For a patient who has blast phase CML, chronic myeloid leukemia behaves more like an acute—or fast-growing—form of leukemia, very different from the slow-growing disease of the chronic phase.
In the blast phase, there are many more leukemia cells in the bone marrow and blood, and they're multiplying much faster. The leukemia cells may spread beyond the bone marrow to other tissues and organs of the body.
A blast crisis is a serious condition that happens if you have 20% or more blast cells along with fever, fatigue, and an enlarged spleen. The goal, as with the accelerated phase, is to get back to chronic phase. In many cases, patients who are in blast crisis undergo a stem cell transplant or get enrolled in a clinical trial.
Blast Phase
Blast cells accumulate and CML behaves like acute leukemia (the more common form).
| Symptoms |
Percentage of Blast Cells in the Blood |
Treatment Goals |
| Fever, fatigue, enlarged spleen, weight loss |
At least 20%
(the more aggressive phase) |
Regain control of disease and return to the chronic phase |