[Stratification therapy in patients with acute promyelocytic leukemia after a complete remission by all-trans retinoic acid].

Objective To explore an efficacious protocol for the patients with acute promyelocytic leukemia (APL) after a complete remission (CR) by all-trans retinoic acid (ATRA).Methods A total of 32 APL patients with an induction of CR by ATRA at our hospital from January 2000 to October 2007 received conventional standard chemotherapy as a consolidation regimen.Stratified according to age, those under 50 years old received an intermediate dose of cytarabine(IDAra-C) and over 50 years old non-IDAra-C regimen.Maintenance regimen:all patients received ATRA, arsenic trioxide (As2O3) and 6-mercaptopurine (6-MP) + methotrexate (MTX) alternately and sequentially for 3 years.The efficacy and side effects of these chemotherapies were observed.Results The median follow-up was 72 (40 - 124 )months.The 5-year disease-free survival (DFS) rates of under 50 years old and over 50 years old were 94.7% and 92.3% respectively.The difference was statistically insignificant ( P ＞ 0.05 ).One patient relapsed after a consolidation therapy and so did another on a maintenance regimen.Thirty patients achieved a constant CR.And 16 of 30 patients completed chemotherapy beyond 5 years and survived disease-free.The 5-year DFS rate of 32 patients was 93.8 %.Conclusion After the achievement of CR with ATRA, all APL patients have a higher rate of DFS after stratification.The side effects are generally mild.Thus a stratification therapy is both feasible and efficacious. Key words: Leukemia, promyelocytic, acute; Cytarabine; Stratification therapeutic method