Chronic graft-versus-host disease and the risk of primary disease relapse: A meta-analysis

•Both PDR and cGVHD have long been the dreaded outcomes for patients with hematologic malignancies.•We conducted a random effect meta-analysis of 11 studies involving 64,239 participants and found a significant decreased risk of developing PDR in patients with cGVHD, with a pooled risk ratio of 0.49 (95% CI: 0.40–0.61, I2 = 69.3%).•We concluded that patients with cGVHD have a significantly lower risk of developing PDR compared with patients without cGVHD.•According to regression meta-analysis, use of ATG and HLA mismatch grafts had a potential modifying effect on the association between cGVHD and PDR. Both primary disease relapse (PDR) and chronic graft-versus-host disease (cGVHD) have long been the dreaded outcomes for patients with hematologic malignancies. Previous theories have speculated an inverse relationship between the two; therefore, we attempted to verify the described association. We searched for titles of articles in MEDLINE (PubMed), Cochrane library, and EMBASE database that evaluated the association between PDR and cGVHD and conducted a random effect meta-analysis of 11 studies involving a total of 64,239 participants. We found a significantly decreased risk of developing PDR in patients with cGVHD, with a pooled risk ratio of 0.49 (95% confidence interval: 0.40–0.61, I2 = 69.3%). We concluded that patients with cGVHD have a significantly lower risk of developing PDR compared with patients without cGVHD.