Squamous Cell Carcinoma, Anus

Synonyms

Epidermoid carcinoma

Definition

Anal squamous cell carcinoma is a malignant epithelial tumor of the anal canal, composed of squamous-type epithelium, showing keratinization and/or intercellular bridges.

Clinical Features

Most patients present with anorectal bleeding. Other symptoms include anorectal pain and mass sensation. Tenesmus and fecal incontinence can suggest tumor invasion into the anal sphincters. Weight loss, inguinal adenopathy, and rectovaginal fistula are indicators of an advanced disease. At presentation, 30–50% of patients have a locally advanced disease with a mean tumor size of 3–4 cm. Clinically suspicious inguinal adenopathy can be found in 10–20% patients during physical examination, and this increases to 30–60% when the tumor is larger than 5 cm. Misdiagnosis and delay in diagnosis are common, because presenting symptoms are often nonspecific and similar to the symptoms of benign anal diseases such as hemorrhoids or fissures.

• Incidence

  Anal squamous cell...