Allogeneic Peripheral Blood Stem Cell Transplantation Significantly Increases Risk of Chronic Graft-versus-Host Disease of Lung Compared with Bone Marrow Transplantation

The risk factors for lung chronic graft-versus-host disease (cGVHD) are not fully elucidated. We attempted to identify clinical risk factors for lung cGVHD after allogeneic hematopoietic cell transplantation (HCT). A total of 401 patients who underwent allogeneic HCT between 2000 and 2007 at Princess Margaret Hospital, Toronto, Canada, were evaluated for lung cGVHD serially starting on day 120 and then annually therafter. The stem cell source for HCT was peripheral blood stem cells (PBSCs) in 280 patients (69.8%) and bone marrow (BM) in 121 patients (30.2%). With a median follow-up of 36.8 months, 68 patients (17%) had a diagnosis of lung cGVHD, with a median time of onset of 11.4 months after HCT. Stem cell source was the sole risk factor identified in univariate analyses. The incidence of lung cGVHD was significantly higher in the patients receiving PBSCs (14.2% at 1 year and 22.7% at 2 years) compared with those receiving BM (6.8 at 1 year and 14.9% at 2 years; hazard ratio, 1.937; P = .02). Multivariate analyses also confirmed the use of PBSCs as an independent risk factor for lung cGVHD (hazard ratio, 2.408; 95% confidence interval, 1.289-4.496; P = .0058). The use of PBSCs is associated with an increased risk of lung cGVHD compared with the use of BM for allogeneic HCT.