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  • • Located at or outside the anal verge

    • Usually well-differentiated, keratinizing tumors

    • Behave similarly to squamous cell carcinomas of skin

    • Lesions may be present for long periods before symptoms develop

    • 4 types

    • -Squamous cell

      -Basal cell

      -Bowen disease

      -Paget disease


  • • Squamous, basal cell carcinoma, and Bowen disease more common in men

    • Paget disease more common in women

    • 50% patients with Paget disease have coexistent GI malignancy

Symptoms and Signs

  • • Mass

    • Bleeding

    • Pain

    • Discharge

    • Itching

    • Tenesmus

    • Lesions may be quite large with central ulceration

    Paget disease: Erythematous, eczematoid rash

    Basal cell: Raised edges with central ulcer

    Bowen disease: Scaly, erythematous, sometimes pigmented; often associated with condylomas in younger patients

Laboratory Findings

  • • Pap smear screening may be useful to detect dysplasia in immunocompromised patients

Imaging Findings

  • CT/MRI: Reveal anal mass

    Endorectal US: Reveals size and depth of invasion and perianal nodes

  • • Chronic or nonhealing perineal ulcer

    • Anal canal cancer

    • Perianal abscess

Rule Out

  • • Biopsy all chronic or nonhealing perineal ulcers

  • • Physical exam with digital rectal exam

    • Assessment for lymph adenopathy (groins)

    • Exam under anesthesia, anoscopy with biopsy

    • Endorectal US to assess size and depth of invasion

    • Chest film, CT to assess for metastatic disease

When to Admit

  • • Intractable symptoms: Pain

    • Severe bleeding with hemodynamic compromise

  • • Mainstay of treatment is surgical (wide excision)

    • Chemoradiation useful for aggressive lesions



  • • Small, well-differentiated lesions (< 4 cm) may be treated with wide excision

    • Large, deep lesions involving sphincters require abdominoperineal resection (APR)

    • Grossly involved lymph nodes should be resected

    • Recurrences may be treated with reexcision or APR

    For Bowen disease: Wide local excision and 4-quadrant biopsy

    For Paget disease: Wide local excision and multiple perianal biopsies


  • • Chemoradiation may have a role in advanced disease

Treatment Monitoring

  • • Surveillance physical exam with rectal exam and lymph node exam


  • • Infection/perianal sepsis

    • Fistula


  • Squamous cell carcinoma: T stage determines survival; 5-year survival T1 (100%), T2 (60%)

    Basal cell carcinoma: Metastasis is rare; local recurrence is 30%

    Bowen disease: invasive squamous cell carcinoma develops in fewer than 10% of cases


Peiffert D et al: Conservative treatment by irradiation of epidermoid carcinomas of the anal margin. Int J Radiat Oncol Biol ...

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