Perianal Paget's Disease.

A 78-year-old woman with a complaint of fecal incontinence was noted to have a perianal rash. Despite improvement of the incontinence with medical management, the rash persisted. She had no symptoms related to the rash, but due to its persistence after two years, she saw a dermatologist who performed a punch biopsy of the area. The biopsy revealed extramammary Paget’s disease that was positive for CAM5.2, CK7, and CDX2 and equivocal for CK20. On physical examination, she had a 2×3cm raised and erythematous lesion on the right buttock extending to the anal margin without anal canal involvement (see Figure 1). Subsequent work-up including upper endoscopy, colonoscopy, CT of the chest and abdomen and pelvis, and small bowel follow through was negative. This patient’s case was discussed at the multi-disciplinary conference, and wide local excision was recommended. The patient underwent wide local excision with healing via secondary intention. Closure was foregone due to the small size of the wound and the patient’s medical comorbidities. Pathological examination confirmed negative margins.