Role of Age and Hematopoietic Cell Transplantation-Specific Comorbidity Index in Myelodysplastic Patients Undergoing an Allotransplant: A Retrospective Study from the Chronic Malignancies Working Party of the European Group for Blood and Marrow Transplantation.

Allogeneic hematopoietic stem cell transplantation (HSCT) remains the only potentially curative option for myelodysplastic syndromes (MDSs) but is severely limited by nonrelapse mortality (NRM), especially in this mostly older population. Comorbidity assessment is crucial to predict NRM and often assessed with the Hematopoietic Cell Transplantation-Specific Comorbidity Index (HCT-CI). Moreover, the impact of age on NRM still remains a matter of debate. In recent years, the age at which transplants are made has been progressively increasing, and patients with comorbidities have become more common. Extricating the respective roles of age and comorbidities in toxic mortality is all the more important. This study by the European Group for Blood and Marrow Transplantation registry included 1245 adult patients who underwent a first allogeneic stem cell transplantation for MDSs between 2003 and 2014. Overall, 4-year NRM and overall survival were 32% and 47%, respectively. When considered as continuous predictors, HCT-CI score and age were associated with an increased hazard ratio (HR) for NRM. In multivariate analysis, age band (HR, 1.13; 95% CI, 1.02 to 1.25; P= .016), HCT-CI ≥3 (HR, 1.34; 95% CI, 1.04 to 1.73; P = .022), and Karnofsky Performance Status ≤80 (HR, 2.03; 95% CI, 1.52 to 2.73; P< .0001) were significantly predictive of a worse NRM. In our large cohort, both comorbidities, evaluated by the original HCT-CI score, and chronological age significantly affected NRM. Thus, age should be part of the transplant decision-making process and should be integrated in future scoring systems predicting outcomes of HSCT in MDSs.