Overall survival (%) of post-transplant lymphoproliferative disorder under 5 prognostic factors following allogeneic stem cell transplantation. Significance is based on log-rank statistics, (A) stratified by Epstein-Barr virus (EBV) DNAemia copies, P=0.033; (B) stratified by Eastern Cooperative Oncology Group (ECOG) score standard, P=0; (C) stratified by infection, P=0.001; (D) stratified by EBV negative or positive after 2 doses rituximab treatment, P=0.003; (E) stratified by gender, P=0.099.