All-trans retinoic acid in association with low dose cytosine arabinoside in the treatment of acute myeoid leukemia in elderly patients.

All-trans retinoic acid (ATRA) has shown a synergistic activity in combination with cytosine arabinoside in vitro in the treatment of acute myeloid leukaemia (AML). In this paper we report the results of treatment with low dose cytosine arabinoside (LDAC) with or without ATRA in 28 patients with acute myeloid leukaemia aged over 60 years: 14 patients received only LDAC and the other 14 LDAC + ATRA. The patients of the 2 groups showed similar clinical features: in 10 patients AML developed after a myelodysplastic form and 4 patients presented a previous malignancy. All the patients received subcutaneous (sc) LDAC (15 mg twice a day for 14 days) and in 14 patients oral ATRA (45 mg/sqm in the same days) was added to LDAC; the courses were repeated every 4 weeks from diagnosis to relapse. The treatment was well tolerated and the patients could self-administer sc LDAC and oral ATRA at home. No statistically significant differences were observed in complete remission rate (21% vs. 50%, respectively) and resistant rate (57% vs. 29%), but the patients treated with the combination of the 2 drugs had a better time to treatment failure (15 weeks vs. 30 weeks, respectively) (P = 0.045) and a longer survival (37 weeks vs. 66 weeks) (P = 0.019). Our experience, although with a low number of patients, confirms the efficacy of ATRA in combination with sc LDAC in the treatment of AML in elderly patients.