Anal Cancer and Anal Cancer precursors in Women with a History of HPV-Related Dysplasia and Cancer.

The epidemiology of anal cancer in the U.S. has changed over the past 3 decades. During this period the incidence of anal cancer has increased among both men and women. Of note, women with a history of anogenital HPV infection are at higher risk than the general population for anal cancer. The increased risk ranged from increased incidence rate ratios ranging from 1.82 to 6.3 in women with a history of cervical cancer, to 4.2-16.4 in women with a history of prior cervical intraepithelial neoplasia 3 (CIN 3). In addition, studies describing screening women with a previous history of anogential HPV infection (including CIN 3) for anal HPV and anal pre-cancers demonstrate that the prevalence of anal HPV is measureable in this population. The prevalence of anal high grade squamous intraepithelial lesions (HSIL) in this population was relatively low, which may have been related to the fact that many of these studies had insufficient samples, and the numbers of patients undergoing HRA remain low. Future studies evaluating anal cancer screening strategies in this high-risk group are needed.