[Treatment of promyelocytic leukemia with retinoic acid: results in Cuba].

PURPOSE: To assess the results attained with all-trans-retinoic acid (ATRA) in a group of Cuban patients with acute promyelocytic leukaemia (PML). PATIENTS AND METHODS: Twenty-one patients with PML were studied. Their cytogenetic study was performed with G-band techniques. ATRA was given orally as a single dosis of 50 mg/m2 a day, or divided in two doses. After attaining complete remission (CR), ATRA was maintained for 1-3 months in association with minimal doses of Ara-C or alpha-interferon. A rotation of three therapeutic regimes (TRAP, POMP and DOAP) was subsequently administered. RESULTS: Twelve of the patients were women and 9 men; 15 were adults and 6 were children, the median age being 19 years (range: 6-60 years). Only two patients had leucocytosis, all others presented with leucopenia. Platelet count below 30 x 10(10)/L was found in 67% of the cases, while some sort of bleeding was present in 81% of them. Laboratory evidence of disseminated intravascular coagulation was seen in 52% of the cases, and t (15; 17) appeared in 67% of the evaluable cytogenetic studies. CR was attained in 17 patients (81%) within a mean of 40 days. Headache was the commonest untoward effect of the treatment. Eight patients developed leucocytosis during treatment, white-cell count being over 20 x 10(9)/L in six of them. Fever without infectious signs was present in 5 patients, and in 3 of them the temperature recovered with steroid therapy. Two patients had retinoic acid syndrome prior to achieving CR. Four patients relapsed and 13 (76%) have maintained CR after 1 to 24 months. CONCLUSIONS: The incidence of CR in this series is within the limits reported in the literature. The secondary effects of the treatment are the same than those reported by others, and they were transient and well tolerated. The response to steroids of those patients with fever secondary to ATRA is noteworthy. The efficacy of ATRA, in general terms, in the induction of CR in PML seems confirmed by these results.