Effects of acute and chronic graft-versus-myelodysplastic syndrome on long-term outcomes following allogeneic hematopoietic cell transplantation

Purpose: Potent graft-versus-tumor (GVT) effects associated with graft-versus-host disease (GVHD) might be dependent on hematologic disease type and status. However, the data regarding the impact of GVHD on transplant outcomes for patients with myelodysplastic syndrome (MDS) are limited. Experimental Design: We retrospectively evaluated the impact of acute and chronic GVHD on transplant outcomes for a large cohort of adult patients with a low-risk (n ¼ 1,193) and high-risk (n ¼ 1,926) MDS treated by first allogeneic hematopoietic cell transplantation between 2001 and 2017. Results: The multivariate analysis, in which development of GVHD was treated as a time-dependent covariate, showed that acute and chronic GVHD at any grade or severity did not improve overall mortality, relapse, or nonrelapse mortality (NRM) in low-risk MDS. For patients with high-risk MDS, development of limited chronic GVHD was significantly associated with lower overall mortality [HR, 0.66; 95% confidence interval (CI), 0.50-0.86; P ¼ 0.002]. This is probably due to that the reduced risk of relapse with grade III-IV acute GVHD (HR, 0.41; 95% CI, 0.25-0.65; P ¼ 0.0002), or limited (HR, 0.57; 95% CI, 0.39-0.83; P ¼ 0.003) or extensive (HR, 0.56; 95% CI, 0.41-0.77; P ¼ 0.0004) chronic GVHD was offset by increased NRM with grade III-IV acute GVHD or extensive chronic GVHD in high-risk MDS. Conclusions: These data demonstrated a survival benefit of the graft-versus-MDS effect is present only in high-risk MDS patients with limited chronic GVHD.