GSTP1 and cancer: In light of the ubiquity of 341C>T polymorphism and the critical role of GSTP1 in the carcinogenic process, we performed a meta-analysis on all eligible case-control studies to estimate the cumulative cancer risk of this polymorphism, and quantitatively analyze the potential influencing factors, with an expectation to provide the most comprehensive evidence for the relationship between this variant and cancer susceptibility.