Is there association between Trichomonas vaginalis infection and prostate cancer risk?: A systematic review and meta-analysis.

We performed a systematic review and meta-analysis to reveal the association between Trichomonas vaginalis (TV) infection and the risk of prostate cancer (PCa) development. Systematic searching (PubMed/Medline, Scopus, Embase, Web of Science, Cinhal, Wiley, Cochrane, Psychoinfo, ProQuest and Google Scholar) was done, up to March 2018 for case-control studies. Random effects model was applied to define odds ratios and their 95% confidence intervals. In total, 6 enteries were included in our meta-analysis, comprising 5590 individuals (2677 PCa cases and 2913 control individuals) examined for trichomoniasis, with a total positivity of 469 (17.51%) and 482 (16.54%) individuals, respectively. Totally, such association was documented in three countries, including USA (4 studies), Kuwait (one study) and Taiwan (one study). Based on pooled estimations, however a 1.17-time increase of PCa was observed among individuals with a previous exposure of TV, it was not statistically significant [OR = 1.17 (95% CI: 1.01 to 1.36)]. Egger's regression test demonstrated no publication bias among studies. Also, year of publication for included records was not significantly correlated to the relationship between trichomoniasis and PCa. Any further inferences should be based on future investigations for better understanding this relationship and shedding light on the cryptic pathogenesis of TV in PCa patients.