gastrointestinal disorders
Anal Cancer
Introduction
Anal cancer accounts for an estimated 9760 cases and about 1870 deaths in the United States annually ( General reference ). The main symptom is bleeding with defecation. Diagnosis is by endoscopy. Treatment options include excision and chemotherapy and radiation therapy. Squamous cell carcinoma (nonkeratinizing squamous cell or basaloid carcinoma) is the most common cause of cancer of the anorectum. Basal Cell Carcinoma , Risk factors for anal cancerinclude the following: Human Papillomavirus (HPV) Infection None Chronic Anorectal Fistula None Irradiated anal skin Premalignant (dysplastic) changes None Lymphogranuloma Venereum (LGV) infection Human Papillomavirus (HPV) Infection infection Smoking People having receptive anal intercourse are at increased risk. Patients with HPV infection may manifest dysplasia in slightly abnormal or normal-appearing anal epithelium (anal intraepithelial neoplasia—histologically graded I, II, or III). These changes are more common among patients with HIV-infection (see Squamous cell carcinoma of the anus or vulva ). Higher grades may progress to invasive carcinoma. It is unclear whether early recognition and eradication improve long-term outcome; hence, screening recommendations are unclear. 