Anal Carcinoma

Anal carcinoma accounts for less than 2% of all gastrointestinal malignancies. The incidence of anal cancer is increasing and may be associated with an increase in anal receptive intercourse or higher number of sexual partners. Such behaviors have also increased the risk of infection with both HIV and human papilloma virus (HPV). HPV appears to induce dysplasia in the anal mucosa, which is readily detectable and treatable. The strong association of HPV has even spurred research into primary prevention in high-risk patients. Models suggest that screening in the highest risk patients would not only confer a survival benefit but also be cost effective. While the overall prognosis is only a 55% survival at 5 years, survival for localized disease remains near 80%. Traditional staging by cross-sectional imaging may be giving way to endorectal ultrasound and sentinel node biopsy. The standard of care for anal canal carcinoma is now combined modality therapy (CMT) with chemoradiation therapy obtaining excellent oncologic results as well as organ preservation. Advances in intensity modulated radiation therapy (IMRT) and brachytherapy have significantly decreased toxicity. Surgery improves survival in patients with persistent or residual disease Within the next decade, anal cancer may emerge as a preventable form of cancer.