Human papillomavirus and risk of prostate cancer: a systematic review and meta-analysis.

Background: There is growing evidence showing a putative association between high-risk human papillomavirus (HR-HPV) infection and an increased risk of PCa.Objective: The aim of the current meta-analysis was to evaluate the association between HPV infection and PCa risk.Methods: This analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. We included all studies on HPV DNA or antibodies detected in biopsy tissues or sera. Available data were extracted from the article, including means and standard deviations in all case-control groups.Results: Thirty studies that investigated the link between HPV-16 and -18 were identified as eligible for this systematic review and meta-analysis, including a total of 6321 participants. The pooled OR showed increased risk of PCa (OR =1.37; p < .01) in men positive for HPV-16. There were seven studies with 2391 PCa cases and 4059 controls investigating the association between HPV-18 infection and PCa risk. Significant heterogeneity between study was found in the pooled analyzes. The pooled OR did not show increased risk of PCa (OR =0.80; p = .49) in men positive for HPV-18.Conclusions: This meta-analysis suggests that HPV-16 infection could represent a risk factor for PCa, whereas we found no such association for HPV-18. Further well-conducted studies could be useful to confirm this conclusion.