Acute transformation of chronic myelomonocytic leukaemia: a multivariate study of predictive factors.

In an attempt to determine the possible predictive value of the main clinical and haematological initial features of chronic myelomonocytic leukaemia (CMML) on the evolution to acute leukaemia, as well as the real impact of such an event on survival, 35 such patients were submitted to multiple regression analyses. At the time of the study 30 out of the 35 patients had died, with a median survival of 8.2 months for the whole series. 12 patients (34%) developed acute leukaemia, between 1.5 and 42.1 months from diagnosis of CMML, the actuarial median time of acute transformation being 29.4 months. The initial bone marrow blast cell percentage was the only factor influencing the development of acute leukaemia. On the other hand, the multivariate survival study showed that acute transformation introduced in the model as a time-dependent variable had a clear-cut unfavourable influence on the outcome of CMML patients, as did palpable spleen, advanced age and marked monocytosis.