Selenium concentration, dietary intake and risk of hepatocellular carcinoma – a systematic review with meta-analysis

Abstract

Aim: this study was performed to investigate the association between selenium concentrations, dietary intake, and the risk of hepatocellular carcinoma (HCC). Methods: we identified eligible studies in PubMed and EMBASE databases, in addition to the reference lists of original studies and review articles on this topic, up to 1 Feb 2019. A summary of standardized mean differences (SMD) with 95% confidence intervals (CI) was calculated using a random-effects model. Heterogeneity between studies was assessed using Cochran Q and I2 statistics. Results: finally, a meta-analysis showed that dietary intake of selenium and tissue selenium concentration were not associated with HCC risk (dietary SMD =-0.11, 95% CI:-0.26 to 0.03; tissue SMD =-0.12, 95% CI:-0.56 to 0.33). However, samples from toenail, whole blood, and serum all showed an inverse association with HCC risk (toenail SMD =-0.53, 95% CI:-0.72 to-0.35; whole blood SMD =-2.21, 95% CI:-2.67 to-1.76; tissue SMD =-1.26, 95% CI:-1.71 to-0.81). Dose-response data from few studies showed that an extra increase in serum selenium was dramatically related with a lower risk of HCC (adjusted p-trend < 0.05). This study showed that selenium concentration in toenail, whole blood and serum was inversely associated with HCC risk. Conclusion: increased concentration in serum selenium was related to a lower risk of HCC. However, these results based on dietary intake and tissue samples, which included few studies, did not reach statistical significance.