Anal Cancer and Anal Cancer Screening.

This chapter provides an overview of anal cancer and contemporary approaches for anal precancer detection, beginning with a discussion of the biology and natural history of anal squamous cell carcinoma, the predominant human papillomavirus -associated histologic subtype of anal cancer. This section is followed by a description of the epidemiology of anal cancer, including trends in incidence and mortality, a discussion of populations with elevated risk for anal cancer and an overview of associated risk factors. The remainder of the chapter provides the most up-to-date evidence on tools and approaches for anal cancer prevention, screening, and early detection; including, the role of human papillomavirus vaccination for primary prevention; anal cytology, high resolution anoscopy and novel biomarkers for secondary prevention; and digital anal-rectal examination for early detection.