Tumor necrosis factor alpha-238G/A polymorphism and risk of breast cancer: An update by meta-analysis

BACKGROUND: The association between the tumor necrosis factor-alpha gene (TNF-a) -238G/A polymorphism and the breast cancer has been analyzed in several studies, but the results have been inconclusive. We then performed a meta-analysis to get a precise estimation of the association. METHODS: Eight case–control studies with a total of 37,257 cases and 39,564 controls were identified by searching the ISI Web of Knowledge database and the PubMed database up to August 2014. RESULTS: Overall, no association was found between TNF-alpha-238G/A polymorphism and breast cancer in any of genetic model (additive model OR = 1.06, 95%CI: 0.94–1.21, P(heterogeneity) = .02; homozygous model OR = 1.04, 95%CI: 0.83–1.30, P(heterogeneity) = .98; dominant model OR = 1.06, 95%CI: 0.92–1.21, P(heterogeneity) = .01; recessive model OR = 1.04, 95%CI: 0.83–1.30, P(heterogeneity) = .98). Furthermore, no significant association was identified when stratified by ethnicity (Caucasian, Asian). CONCLUSION: This meta-analysis indicated that the TNF-alpha-238G/A polymorphism is not associated with breast cancer risk in the overall population.