Incidence of GVHD. (A) Cumulative incidence at day 100 of aGVHD grade 2 to 4. (B) Cumulative incidence at day 100 of aGVHD grade 3 to 4. (C) Cumulative incidence of cGVHD at 5 years among patients with MDS who received PTCY or ATG as GVHD prophylaxis for UD allo-HSCT. Numbers below the graph show the number of patients at risk.