Prevalence of anal human papillomavirus infection and anal HPV-related disorders in women: a systematic review

Abstract

The aim of this study was to systematically review the findings of publications addressing the epidemiology of anal human papillomavirus (HPV) infection, anal intraepithelial neoplasia, and anal cancer in women. We conducted a systematic review among publications published from Jan. 1, 1997, to Sept. 30, 2013, to limit to publications from the combined antiretroviral therapy era. Three searches were performed of the National Library of Medicine PubMed database using the following search terms: women and anal HPV, women anal intraepithelial neoplasia, and women and anal cancer. Publications were included in the review if they addressed any of the following outcomes: (1) prevalence, incidence, or clearance of anal HPV infection, (2) prevalence of anal cytological or histological neoplastic abnormalities, or (3) incidence or risk of anal cancer. Thirty-seven publications addressing anal HPV infection and anal cytology remained after applying selection criteria, and 23 anal cancer publications met the selection criteria. Among HIV-positive women, the prevalence of high-risk (HR)-HPV in the anus was 16-85%. Among HIV-negative women, the prevalence of anal HR-HPV infection ranged from 4% to 86%. The prevalence of anal HR-HPV in HIV-negative women with HPV-related pathology of the vulva, vagina, and cervix compared with women with no known HPV-related pathology, varied from 23% to 86% and from 5% to 22%, respectively. Histological anal high-grade squamous intraepithelial lesions (anal intraepithelial neoplasia 2 or greater) was found in 3-26% of the women living with HIV, 0-9% among women with lower genital tract pathology, and 0-3% for women who are HIV negative without known lower genital tract pathology. The incidence of anal cancer among HIV-infected women ranged from 3.9 to 30 per 100,000. Among women with a history of cervical cancer or cervical intraepithelial neoplasia 3, the incidence rates of anal cancer ranged from 0.8 to 63.8 per 100,000 person-years, and in the general population, the incidence rates ranged from 0.55 to 2.4 per 100,000 person-years. This review provides evidence that anal HPV infection and dysplasia are common in women, especially in those who are HIV positive or have a history of HPV-related lower genital tract pathology. The incidence of anal cancer continues to grow in all women, especially those living with HIV, despite the widespread use of combined antiretroviral therapy.

Keywords: anal cancer; anal intraepithelial neoplasia; epidemiology; human papillomavirus; systematic review.

Figure 1. Systematic Review Process for searching Published Literature with Defined Search Terms from January 1, 1997 through September 30, 2013