[Multivariate analysis of prognostic factors influencing survival in chronic myelogenous leukemia]

Prognostic significance of disease features obtained at the time of initial diagnosis was analyzed in 90 patients with chronic myelogenous leukemia (CML) in chronic phase. Median survival of this population was 45.9 months. Univariate analysis revealed that splenomegaly, bone marrow basophils, bone marrow blasts, peripheral blood blasts, and bone marrow eosinophils were significant prognostic factors for survival, and that peripheral blood leukocytes counts, hemoglobin concentration, performance status, age and lymphadenopathy were factors with border line significance. There were multiple interrelationship among these disease features. Multivariate regression analysis identified that age, hemoglobin concentration, and bone marrow blasts were independent primarily significant prognostic factors for survival. The Cox model generated with three variables of age, hemoglobin concentration, and percent blasts in bone marrow provided a useful representation of risk status in the population. A hazard function derived from the patients population segregated patients into three groups with significantly different survival patterns: A lower risk group, an intermediate group and a high risk group of patients with median survival of 57.8, 49.8 and 38.4 months respectively. Survival after CML blast crisis was short and overall median survival of 54 patients with CML blast crisis was 6.4 months. A sole prognostic factor for survival in blast crisis identified by multivariate analysis was blast cell type at CML blast crisis and patients with lymphoid phenotype had a good prognosis with median survival of 9.8 months. Median survival of myeloid crisis was 4.2 months. No other disease features were identified as significant prognostic factors in the present patient population.