Age adjusted hematopoietic stem cell transplant comorbidity index predicts survival in a T-cell depleted cohort

Objectives: Allogeneic hematopoietic stem cell transplant (HCT) continues to evolve with the treatment in higher risk patient population. This practice mandates stringent update and validation of risk stratification prior to undergoing such a complex and potentially fatal procedure. We examined the adoption of the new comorbidity index (HCT-CI/Age) proposed by the Seattle group after the addition of age variable and compared it to the pre-transplant assessment of mortality (PAM) that already incorporates age as part of its evaluation criteria. Methods: A retrospective analysis of adult patients who underwent HCT at our institution from January 2010 through August 2014 was performed. Kaplan-Meier's curve, log-rank tests, Cox model and Pearson correlation was used in the analysis. Results: Of the 114 patients that underwent allogeneic transplant in our institution, 75.4% were ≥40 years old. More than 58% had a DLCO ≤80%. Although scores were positively correlated (correlation coefficient 0.43, p < 0.001), HCT-CI/Age more accurately predicted 2-year overall survival (OS) and non-relapse mortality (NRM) in patients with lower (0–4) and higher (5–7) scores (52% and 36% versus 24% and 76%, p = 0.004, 0.003 respectively). PAM score did not reach statistical significance for difference in OS nor NRM between the low (<24) and high-risk (≥24) groups (p = 0.19 for both). Conclusions: Despite our small sample population, HCT-CI/Age was more discriminative to identify patients with poor outcome that might benefit from intensified management strategies or other therapeutic approaches rather than allogeneic HCT.