An 84-year-old Korean man with hypertension and a history of appendectomy presented with perianal pruritus and a rash. He was treated with topical and oral medications at a local dermatologic clinic for a year, but his clinical symptoms did not improve. He visited Severance Hospital and underwent a perianal skin biopsy, and was finally diagnosed with EMPD. The 6.5 cm² × 8 cm²-sized skin lesion was oval shaped and located from under the coccygeal area to the perineal body. The lesion abutted the anoderm 1 cm from the anal verge, but had not invaded the penis, testes, or both thighs. Abdomino-pelvic computed tomography and rectal magnetic resonance imaging were performed to evaluate preoperative staging and to detect other diseases. They showed no abnormalities, including no regional and inguinal lymph-node enlargement. A colonoscopy showed no intraluminal abnormalities. Thus, the authors decided to perform a wide local excision and to make flaps for the large area of skin and the soft tissue defects.

The patient received a bowel preparation with polyethylene glycol one day before surgery because of the possibility of conversion to an abdominoperineal excision. He was placed in a jack-knife position on the table (Fig. 1A). Surgical margins 1 cm around the main lesion were demarcated based on a preoperative multiple-punch biopsy at eight locations which were all proven to be basal pigmentation or eczematous change. A wide local excision was performed (Fig. 1B). The size of the lesion was 6.5 cm² × 8 cm². However, we carefully resected the lesion over the demarcation because the patient was too old to tolerate the time required for the frozen biopsy to confirm the proper margins. As a result, the final size of the specimen was 9 cm × 14 cm (Fig. 1C). For the skin and the soft tissue defects, bilateral inferior gluteal artery perforator flap transpositions were performed (Fig. 1D). Two closed suction drains were inserted at both flap sites. Repair and reinforcement of the dentate line with the skin were performed. A 28-Fr rectal tube was inserted into the anal canal. Aseptic dressing was done, and the patient was sent to the recovery room without any events. The total operation time was 182 minutes, and the estimated blood loss was 20 mL.

The patient recovered without any complications. He sustained the prone position for the integrity of flaps and was kept on nil per os (nothing by mouth) with intravenous nutritional support alone for 12 days after surgery to prevent wound infection from the stool. The right drain was removed at postoperative day (POD) #6 whereas the left drain was removed at POD #12. The rectal tube was removed at POD #7. The patient started his diet at POD #13 without any problems. The pathology was proven as EMPD. The immunohistochemistry was positive for cytokeratin 7 (CK7), carcinoembryonic antigen, and C-erb B2 while it was negative for HMB-45 (Fig. 2). The lateral and the basal margins were all disease free (0.7 cm and 0.1 cm, respectively). The patient was discharged at POD #20.