A MULTIVARIATE-ANALYSIS OF PROGNOSTIC FACTORS IN CHRONIC MYELOID-LEUKEMIA

Abstract

The prognostic value of different clinical and laboratory findings at diagnosis of chronic myeloid leukemia (CML) was analyzed in 121 cytogenetically studied patients. From the univariate and multivariate analysis of the whole series, it was apparent that the minority of Ph1[Philadelphia chromosome]-negative patients (11.5%) could be considered as a poor prognosis group. The analysis was then restricted to the Ph1-positive patients. From a multivariate survival analysis (Cox''s regression model) of the latter group, poor prognosis factors emerged as follows: splenomegaly, hepatomegaly, presence of erythroid precursors in peripheral blood and bone marrow myeloblasts > 5%. From the contribution of each one of these factors to the regression model, a clinical staging of Ph1-positive CML was derived as follows: stage I (low risk, 32% of patients), including patients with 1 or 0 factors; stage II (intermediate risk, 38%), including cases with 2 factors; and stage III (high risk, 30%), including patients with 3 or 4 factors. The difference in survival of the patients at different stages was highly significant (P < 0.001).