Delay in the administration of all-trans retinoic acid and its effects on early mortality in acute promyelocytic leukemia: final results of a multicentric study in the United States.

Early death (ED) occurs in 10-30% of patients with acute promyelocytic leukemia (APL). Is all-trans retinoic acid (ATRA) promptly given and does it decrease overall early mortality? ATRA was administered within 24h of morphological suspicion in only 44% of the 120 consecutive patients treated in the four collaborating centers. Absence of disseminated intravascular coagulation (p=0.012) and admission to a non-university-affiliated hospital (p=0.032) were independent predictors of ATRA delay. ED occurred in 17% of patients, and was independently correlated only with ICU admission (p=0.002). Our results do not demonstrate that prompt (versus delayed) ATRA administration decreases overall early death.