The benefit of chronic graft-versus-host disease in patients with acute myeloid leukemia relapsed after allogeneic stem cell transplantation

To investigate the effect of chronic graft-versus-host disease (cGVHD) on the outcomes of acute myeloid leukemia (AML) patients who relapsed after allogenic hematopoietic cell transplantation, we performed a retrospective analysis on 218 patients with a median follow-up of 21.4 (3.4–179.6) months. A total of 103 patients developed cGVHD, with a 2-year cumulative incidence of 48.9% (95% CI 42.1–55.7%). The estimated 3-year overall survival was 85.7% (95% CI 75.7–95.7%), 48.8% (95% CI 31.7–66.0%), and 54.1% (95% CI 44.3–63.8%) for patients with limited cGVHD, extensive cGVHD, and without cGVHD (P < 0.001). The 3-year event-free survival were 75.5% (95% CI 63.7–87.4%), 46.0% (95% CI 28.8–63.2%), and 45.0% (95% CI 35.6–54.4%) (P < 0.001), while the 3-year cumulative relapse rates were 22.8% (95% CI 11.0–34.6%), 11.6% (95% CI 5.3–22.6%), and 40.3% (95% CI 31.0–49.6%), respectively (P < 0.001). At the last evaluation, 62 patients relapsed with 17 patients having active cGVHD and 45 without. Compared to patients relapsing without cGVHD, patients who relapsed with cGVHD had a longer duration of remission and a better 2-year post-relapse survival [10.9 months (3.7–42.2) versus 4.4 months (2.2–28.3); P < 0.001]; [32.8% (95% CI 8.2–57.4%) versus 4.5% (95% CI 0–12.8%); P = 0.043]. For patients who relapsed with cGVHD, the remission rates were both 60% after salvage chemotherapy with or without donor lymphocyte infusion (P = 1.000). In conclusion, cGVHD may exert a stronger graft-versus-leukemia effect, which may decrease the post-transplantation relapse rate and may also benefit those patients who eventually relapsed after transplantation in terms of prolong post-relapse survival.