Long-term follow-up results of the combination of topotecan and cytarabine and other intensive chemotherapy regimens in myelodysplastic syndrome

BACKGROUND. Progressive or higher-risk myelodysplastic syndrome (MDS) is often treated with intensive chemotherapy regimens used for acute myelogenous leukemia (AML). Patients with MDS are often older and may have contraindications to anthracycline-based regimens. Topotecan-cytarabine regimens have shown encouraging results in higher-risk MDS. The aim Of this study was to analyze the long-term results with topotecan-cytarabine versus other intensive chemotherapy regimens in higher-risk MDS. METHODS. Five hundred ten patients with higher-risk MDS treated with intensive chemotherapy were reviewed. Their median age was 63 years; 82% had intermediate 2 or high-risk MDS; 32% had secondary MDS; 40% had chromosome 5 or 7 abnormalities. Therapy was: topotecan-cytarabine in 77; idarubicin-cvrarabine regimens in 270; topotecan-cytarabine and cyclophosphamide in 67; fludarabine-cytarabine in 96. Univariate and inultivariate analyses were conducted to evaluate the independent associations of different variables, and most important, the treatment regimen, with complete response, induction mortality, and survival. RESULTS. The overall complete response (CR) rate was 55%, induction mortality 17%, and 5-year survival rate 8%. The 5-year survival rate was 11% for patients younger than 65 years old and 17% for patients with a normal karvotype. Among 82 patients younger than 65 years with a normal karvotype, the CR rate was 67%, 5-year survival rate 27%, and 5-year CR duration rate 33%. Topotecan-cytarabine regimens were equivalent to idarubicin-cytarabine regimens in relation to CR rates and Survival rates, but were associated with a lower induction mortality. Multivariate analysis confirmed that treatment regimens were not associated with independent significant differences in CR rates or survival. However, topotecan-cytarabine regimens were still selected to be associated with lower induction mortality rates. CONCLUSIONS. This analysis suggests that topotecan-cytarabine regimens are equally effective to other AML regimens in higher-risk MDS and may be less toxic. Topotecan-cytarabine may be considered a reasonable alternative to idarubicin-cytarabine in higher-risk MDS, particularly in older patients with contraindications to anthracyclines.