All-trans retinoic acid significantly reduces the incidence of early hemorrhagic death during induction therapy of acute promyelocytic leukemia.

Early hemorrhagic death (within the first 10 d of treatment [EHD]) is reported as the main cause of death during induction therapy for acute promyelocytic leukemia (APL). In order to evaluate possible differences in the incidence of EHD during induction regimens based on all-trans retinoic acid (ATRA), we retrospectively analyzed a consecutive series of 86 APL patients, diagnosed and treated at our Institution from 1982. Forty-three patients received combination chemotherapy with anthracyclines and cytosine arabinoside (January 1982 to December 1991), while induction of the remaining 43 was based on ATRA alone or on a combination of ATRA and anthracyclines (January 1992 to October 1996). There were significantly less induction deaths in the ATRA group [9 (chemotherapy group-CT) vs. 2 (ATRA group-RA) overall and 8(CT) vs. 1(RA) of EHD; p = 0.01]. Hemostatic evaluations showed an earlier reduction of D-dimer in the ATRA group. No cases of morphological resistance were observed in the ATRA group after induction. In addition, the number of relapses occurring in the first 24 months from the achievement of complete remission (CR) was significantly lower in the ATRA group (15 vs. 7; p = 0.01), with a disease free survival at 2 yr of 67% vs. 31%. In conclusion, ATRA appears to be able to significantly reduce the incidence of EHD, increasing the number of possible long-term remissions.