IL6 and graft versus host disease: We identified a threshold (Figure 2) of 2.5 pg/ml for pre-transplant IL6 levels in correlation with TRM (AUC 0.74; sensitivity 71%, specificity 72%, p < 0.001) and a threshold of 16.5 pg/ml for post-transplant IL6 as predictor of grade II–IV acute GvHD, grade III–IV acute GvHD and TRM (AUC 0.754, sensitivity 76%, specificity 67%, p < 0.001; AUC 0.82, sensitivity 91%, specificity 63%, p < 0.01; AUC 0.69, sensitivity 76%, specificity 57%, p = 0.005, respectively).