Day100 Score predicts moderate-severe cGVHD, transplant mortality, and survival after hematopoietic cell transplantation

: The aim of this study was to develop a predictive score for moderate-severe chronic graft-versus-host disease (cGVHD) on day +100 after allogeneic stem cell transplantation (HSCT). We studied 1292 patients allografted between 1990 and 2016, alive on day +100 after transplant, without cGvHD, and with full biochemistry laboratory values available. Patients were randomly assigned to a training and a validation cohort (ratio 1:1). In the training cohort, a multivariate analysis identified four independent predictors of moderate-severe cGvHD: gammaglutamyltransferase ≥75 UI/l, creatinine ≥1 mg/dl, cholinesterase ≤4576 UI/l and albumin ≤4 g/dl. A score of 1 was assigned to each variable, producing a low (0-1), intermediate (2-3) and high (4) score. The cumulative incidence (CI) of moderate-severe cGvHD was 12%, 20% and 52% (p<0.0001) in the training cohort, and 13%, 24% and 33% (p=0.002) in the validation cohort. The 5 year CI of transplant related mortality (TRM) was 5%, 14%, 27%(p<0.0001) and 5%, 16%, 31%(p<0.0001), respectively. The 5 year survival was 64%, 57%, 54%(p=0.009) and 70%, 59%, 42%(p=0.0008) in the two cohorts respectively . In conclusion, Day100 score predicts cGvHD, TRM and survival, and, if validated in a separate group of patients, could be considered for trials of pre-emptive therapy.