Time to progression of the disease is variable. Evolution from chronic phase to accelerated phase to blast crisis is a natural course of the disease.
Duration of the chronic phase is the major determinant of survival time.
Prognostic factors for adults that predict early transformation:
- Spleen size at diagnosis
- Hepatomegaly
- Thrombocytopenia
- Thrombocytosis
- Platelet count
- Circulating myeloblasts
- Eosinophils and basophil counts
- Blast cell phenotype
- Cytogenetic findings
These prognostic factors cannot be generalized to pediatric CML population.
Survival outcome for blast phase is generally poor and fewer than 15% of patients achieve long-term survival.
Prognostic factors after entering blast phase:
Favourable factors include lymphoblastic phenotype and minimal karyotypic evolution.
