Anal Cancer and Anal Intraepithelial Neoplasia Risk among Patients Treated for HPV-Related Gynecological Diseases—A Systematic Review

Background: The most important causative agent of neoplasms in the anogenital area is the human papillomavirus (HPV). Due to the anatomical proximity of the genital and anus area and the ease with which HPV infection is transmitted, it seems that patients after the treatment of HPV-related gynecological diseases may have an increased risk of developing a second HPV-related neoplasm anal cancer. The aim of this study was to determine the risk of anal intraepithelial neoplasia (AIN) and anal cancer (AC) among patients after the treatment of HPV-related gynecological diseases. Methods: We conducted a comprehensive review of the available literature from multiple databases. The study was performed following Cochrane Reviewers’ Handbook and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009 guidelines. Moreover, we assessed the quality of each study using QUADAS-2. Results: Twenty-five studies were included in the final analysis. Patients after the treatment of HPV-related gynecological diseases have a significantly higher risk of AC (mean standardized incidence ratio (SIR) = 5.387, mean incidence risk (IR) = 0.096%, mean IR per 100,000 person–years = 10.37) and AIN (mean IR = 23.683%) compared to the population risk. Conclusions: patients with HPV-related gynecological diseases should constitute a group for which an appropriate primary and secondary screening for AC should be introduced.