Association between glutathione S-transferase M1 polymorphism and esophageal cancer: a pooled analysis based on Chinese individuals.

Many studies have analyzed the association between between glutathione S-transferase M1 (GSTM1) polymorphism and esophageal cancer, however, the results are inconsistent. This meta-analysis updated and reevaluated the possible associations between GSTM1 polymorphism and susceptibility to esophageal cancer based on Chinese individuals. The PubMed, Springer Link, Ovid, Chinese Wanfang Data Knowledge Service Platform, Chinese National Knowledge Infrastructure and Chinese Biology Medicine were searched up to February 2017. A total of 20 case-control studies including 2113 esophageal cancer cases and 2848 relevant controls were screened out. Overall, the meta-analysis demonstrated significant associations between the GSTM1 null genotype and increased risk for esophageal cancer in the Chinese population. In subgroup analyses, it indicated the similar results in population-based and hospital-based studies, as well as in North China and South China. As for subgroup analysis by histological type, a non-significant association was found in esophageal squamous cell carcinoma. Our study suggested that GSTM1 null genotype might contribute to increased risk of esophageal cancer in Chinese population.