Prognostic factors at relapse for adults with acute myeloid leukemia.

To identify prognostic factors for patients with acute myeloid leukemia in first relapse we have analyzed the courses of 57 patients undergoing intensive reinduction therapy. The median duration of first remission was 9 months. A second complete remission was achieved by 31 patients (54%). The median duration of second remission was 5 months (range 1-142 + months). Two patients are still disease-free with 42 months and 142 months follow-up. Clinical, laboratory, and treatment variables at the time of original diagnosis and at relapse were examined for possible associations with the outcome of reinduction chemotherapy. Only duration of first remission consistently correlated with ability to achieve a second remission, second remission duration, and overall survival from reinduction. The second complete remission rate was 69% for those with a first remission longer than 9 months but only 39% for those with a first remission less than 9 months (P less than 0.05). The patients with longer first remissions also had longer second remissions (8 months median vs. 4 months, P = 0.02) and a longer median survival following reinduction chemotherapy (8 months vs. 5 months, P = 0.02). We conclude that the duration of a patient's first remission should be considered a useful prognostic factor both in treatment planning and in the interpretation of clinical trials of patients in relapse.