Prognostic implication of pre-transplant FEV1 on long-term outcomes following allogeneic hematopoietic stem cell transplantation.

Abstract

Pre-transplant pulmonary function testing (PFT) is essential before allogeneic hematopoietic stem cell transplant (HCT), yet the optimal cutoff value for affecting transplant outcomes remains poorly defined. Retrospective analysis of pre-HCT PFT data from 605 consecutive patients at the Princess Margaret Cancer Centre between January 1, 2004 and December 31, 2013 used binary recursive partitioning to identify cutoff values for overall survival (OS) as an endpoint of transplant outcomes. These values were compared to HCT comorbidity index (HCT-CI) FEV1 cutoffs for OS, cumulative incidence of relapse and non-relapse mortality. FEV1 ≥ 81% was the identified cutoff point. The OS rate at 3 years showed 49.8% (FEV1 ≥ 81%) vs. 36.6% (<81%, p < .001). For HCT-CI cutoffs, the OS rate at 3 years for FEV1 ≥ 80%, 66%-80% and ≤65% were 49.0%, 38.1% and 37.6% (p = .011), respectively. Multivariate analysis confirmed that FEV1 ≥ 81% predicted reduced mortality (HR 0.682, p = .001). Subgroup analysis showed both FEV1 ≥ 81% and FEV1 by HCT-CI cutoffs may stratify patients according to OS and NRM risk in subgroups receiving myeloablative, but not reduced intensity conditioning. FEV1 ≥ 81% can predict OS and NRM in our cohort and is potentially simpler when risk stratifying patients undergoing allogeneic HCT, particularly those receiving myeloablative conditioning.