Combined chemotherapy for acute promyelocytic leukemia: a meta-analysis

Background: This study evaluates the efficacy of combined chemotherapy for the management of acute promyelocytic leukemia (APL).

Method: Literature search was carried out in several electronic databases. Meta-analyses were performed to achieve weighted effect sizes of overall survival (OS), disease-free survival (DFS), complete remission (CR) rate, and relapse rate. Metaregression analyses were performed to evaluate the factors affecting CR and relapse rates.

Results: Data from 37 studies (7566 patients) were used for meta-analysis. Median follow-up was 49.24 [95% confidence interval (CI): 41.33, 57.16] months. Five-year OS and DFS were 86.41 [83.97, 88.85] % and 75.42 [67.44, 83.40] %, respectively (pooled effect size [95% CI]). Following induction therapy, 89.77 [87.04, 92.50] % patients achieved CR in 38.25[37.84, 38.65] days and 6.34 [5.98, 6.70] % of the patients died during induction. Induction with all-trans retinoic acid (ATRA), arsenic trioxide (ATO), and daunorubicin (DNR) combination was associated with the highest rate of CR (96.16 [89.92, 92.40] %), followed by ATRA-DNR (94.29 [93.15, 95.43] %), ATRA-DNR-cytarabine (92.04 [88.38, 95.71] %), and ATRA-idarubicin (91.16 [89.92, 92.40] %). Overall relapse rate in the study population was 14.42 [11.97, 16.86] %. Baseline leukocyte count was inversely related to the CR rate.

Conclusion: Combined chemotherapy for APL is associated with 90% CR, 14.4% relapse rate, 86% 5-year OS, and 75% 5-year DFS. Induction with ATRA-DNR-ATO is found better than other combinations with respect to CR and relapse rates. Initial leukocyte count may affect prognosis.