Multivariable time-dependent analysis of the impact of azacitidine in patients with lower-risk myelodysplastic syndrome and unfavorable specific lower-risk score

• Two scores identify lower-risk patients with survival similar to high-risk patients.
• Achieving response to azacitidine in these patients appears to impact on survival.
• Thrombocytopenia is the most important prognostic parameter in lower-risk MDS.
• This analysis supports a prospective intervention in these poor risk patients.

Scoring systems for lower-risk myelodysplastic syndrome (LR-MDS) recognize patients with a poorer than expected outcome. This study retrospectively analyzes the role of azacitidine in LR-MDS with adverse risk score and compared to an historical cohort treated with best supportive care or erythropoiesis-stimulating agents. Overall response to AZA was 40%. One and 2-year probabilities of survival were 62% and 45% for AZA vs. 25% and 11% (P = 10−4). In a multivariable time-dependent analysis, response to AZA (CR/PR/HI) was associated with an improved survival (HR = 0.234, 95% CI, 0.063–0.0863; P = 0.029). Thrombocytopenia (<50 × 109 L−1) is confirmed as an adverse parameter in LR-MDS (HR = 1.649, 95% CI, 1.012–2.687; P = 0.045).