A Case Series of Anal Carcinoma Misdiagnosed as Idiopathic Chronic Anal Fissure.

Chronic anal fissure is a linear ulcer in the anal canal that has not cicatrized for more than 8-12 weeks of treatment. Most anal fissures are idiopathic and are located in the posterior midline. Squamous cell carcinoma of the anus commonly presents as bleeding and anal pain. It may also present as a mass, nonhealing ulcer, itching, discharge, fecal incontinence and fistulae. Not uncommonly, small and early cancers are misdiagnosed as benign anorectal disorders like anal fissures or hemorrhoids. The clinical suspicion of squamous cell carcinoma of the anus is of paramount importance in patients with nonhealing anal fissures, fissures in atypical positions or with indurated or ulcerated anal tags and in patients with risk factors for the development of anal squamous intraepithelial lesions that are precursors of invasive anal squamous cell carcinoma. The authors present 3 cases of squamous cell carcinoma of the anus initially misdiagnosed as benign chronic anal fissure.