Management of patients with acute non-lymphocytic leukemia who fail first cycle of induction therapy

The charts of 36 newly-diagnosed ANLL patients treated with intensive combination chemotherapy were retrospectively analyzed to see if we could find clinical parameters which would predict those patients who, after failing their initial treatment cycle, would respond to subsequent cycles of the same regimen. Three groups of patients were identified. Twenty-two patients achieved complete remission with one cycle of chemotherapy; seven patients achieved remission with a second cycle of the same regimen and seven did not. These three response groups did not differ significantly with regard to any of multiple pretreatment parameters. Consequently marrow studies obtained following the first cycle of therapy were analyzed. Patients who subsequently responded to the regimen differed from non-responders in the residual blast percentage in the marrow obtained 21 days after the first cycle. Patients who responded to a second cycle had 2-27% blasts (median 7.3), while non-responders had 35-93% blasts (median 58%) (p < 0.01). We conclude that patients with more than 30% blasts in their bone marrow 21 days after the initiation of the first cycle of the chemotherapy regimens used should receive an alternate regimen for their second cycle of induction therapy.