Prognostic value of early response to chemotherapy assessed by the day 15 bone marrow aspiration in adult acute lymphoblastic leukemia: a prospective analysis of 437 cases and its application for designing induction chemotherapy trials.

The early response to induction chemotherapy assessed by the percentage of residual blast cells in the D15 bone marrow aspiration was prospectively evaluated in 437 patients included in the same multicentric trial of newly diagnosed adult acute lymphoblastic leukemia (LALA87). Among them, 286 patients (65.4%) had < or = 5% residual blasts and their complete remission (CR) rate at D28 was 91% while the CR rate at D28 was only 34% for the 151 patients (34.6%) with more than 5% blasts at D15 of the induction chemotherapy. The persistence of more than 5% of blasts was associated with a significantly worse overall survival (P < 0.0001) and worse disease-free survival (P = 0.02). These data are used as a support for simulating different strategies in order to improve CR rates in future clinical trials. Results are consistent with the fact that D15 marrow evaluation might be a relevant test allowing an early intensification of a subgroup of patients predicted to fail with conventional induction chemotherapy.

RCT Entities:   Population Interventions Outcomes