The early reduction of leukemic blasts in bone marrow on day 6 of induction treatment is predictive for complete remission rate and survival in adult acute myeloid leukemia; the results of multicenter, prospective Polish Adult Leukemia Group study.

The aim of this study was to prospectively evaluate the impact of early bone marrow response on complete remission (CR) rate and long-term outcome in adults with acute myeloid leukemia. Bone marrow cytology was assessed on day 6 of induction treatment in 164 patients, revealing the presence of ≥5% blasts in 61 cases. In this subgroup the CR rate was significantly lower compared to the remaining patients (P < 0.00001) resulting in decrease of the overall survival (P = 0.002). Persistence of ≥5% blasts in bone marrow on day 6 of induction is an easily available surrogate marker to be used for treatment decisions.