The addition of all-trans retinoic acid to chemotherapy may not improve the outcome of patient with NPM1 mutated acute myeloid leukemia

Background: Previous studies have suggested that NPM1 mutations may be a marker for response to all-trans retinoic acid (ATRA) given as an adjunct to intensive chemotherapy in older patients with acute myeloid leukemia (AML). Patients and Methods: We examined the impact of the addition of ATRA among patients with diploid cytogenetics treated on a randomized phase II study of fludarabine + cytarabine + idarubicine ± G-CSF ± ATRA with available data on their NPM1 mutation status. Between September 1995 and November 1997, 215 patients were enrolled in the study. Among them, 70 patients had diploid cytogenetic and are the subjects of this analysis. Results: The median age of the 70 patients was 66 years (range 23-87). Twenty (29%) of patients had NPM1 mutations. Among them 7 (35%) did and 13 (65%) did not receive ATRA in combination with chemotherapy. Complete remission (CR) was achieved in 71% of patients treated with ATRA as compared to 69% without ATRA (P = 0.62). With median follow-up of 12.5 years, the overall survival (OS), event-free survival (EFS), and relapse-free survival (RFS) were similar among patients who received ATRA compared to no ATRA regardless of NPM1 mutation status. Conclusion: The addition of ATRA to intensive chemotherapy did not affect the overall outcome of patients with AML regardless of NPM1 mutation status.