抄録
Prostate cancer is one of the most increasing prevalence of cancers in Japan. It is well known that vitamin E acts as a useful chemo-preventive agent against several types of cancers. However there are conflicting results on a role of vitamin E in the prevention of prostate cancer. In this study, a meta-analysis of current evidence from randomized controlled trials (RCTs) was conducted to evaluate the role of vitamin E in the prevention of prostate cancer. Relevant articles in PubMed were systematically searched for RCTs of vitamin E intake and incidence of prostate cancer. From 455 potential articles, 6 eligible RCTs articles were selected. Meta-analysis of 6 RCTs identified showed no significant difference on the effect of vitamin E intake alone on the reduction in incidence of prostate cancer (Relative Risk (RR)=0.88, 95% Confidential Interval (CI): 0.71, 1.08, P=0.22; random effects). However, there was heterogeneity in this meta-analysis, so that this result suggested that vitamin E intake might have a protective effect against prostate cancer in some cases.