A new ultimate anus-preserving operation for extremely low rectal cancer and for anal canal cancer.

To avoid permanent colostomy, we perform a new ultimate anus preserving operation for extremely low rectal cancer or for anal canal cancer. According to our pathologic study, two different removal methods of anal canal were theoretically considered. One is internal sphincter resection (ISR method), and the other is both deep-superficial external sphincter and internal sphincter resection (ESR method). Six patients received ISR and ten patients ESR. No severe intraoperative complications occurred and the postoperative course was uneventful. All patients receiving ISR had excellent anal function without soiling. Some patients receiving ESR sometimes complained of night soiling but satisfied the anus preservation. The median follow-up was 15 months, (range, 3-28 months). We had recurrences in two female patients receiving ISR. One had para-aortic and lateral lymph node recurrences without anastomotic recurrence. She underwent lateral and para-aortic lymphadenectomy, but died of lung metastasis, regardless of intensive chemotherapy. Another had pelvic recurrence with abdominal dissemination. She underwent abdominoperineal resection and is alive with pelvic re-recurrence. ISR and ESR are excellent procedures for anus preservation, but ISR needs a strict indication.