- Clinical science
Anal cancer is a rare tumor. Risk factors include infection with human papillomavirus (HPV), immunodeficiency, and receptive anal intercourse. The most common clinical features are rectal bleeding (up to 45% of cases), pruritus ani, and tenderness or pain in the anal area. Anal cancer presents mainly as squamous cell carcinoma and in rare cases as adenocarcinoma or other non-epidermoid cancers. Depending on the exact localization and stage, it requires excision and/or radiochemotherapy. If the condition is treated in its early stages, the prognosis is favorable.
- Incidence: ∼ 8000 cases diagnosed per year in the U.S.
- More common in HIV-positive individuals and men who have sex with men
Epidemiological data refers to the US, unless otherwise specified.
- Digital rectal exam
- Biopsy for histology (small tumors are fully excised)
- Staging: endosonography, abdominal ultrasound, abdominal CT, pelvic MRI, chest x-ray/CT
- Histology: primarily squamous cell carcinoma; rarely adenocarcinoma or other non-epidermoid cancers
- Above the anal verge → Anal canal tumors
- Below the anal verge → Anal margin tumors
Anal canal cancer
- Treatment of choice: radiochemotherapy
- Recurrent cancers are treated surgically.
- Anal margin cancer