[Efficacy of intersphincteric resection in the sphincter-preserving operation for ultra-lower rectal cancer].

Objective: To evaluate the clinical efficacy of intersphincteric resection in the sphincter- preserving operation for ultra-lower rectum cancer.

Methods: Thirty-one rectal cancer patients with the distal edge of the tumour less than 2 cm from the dentate line were evaluated. Eighteen advanced rectal cancer patients received preoperative chemo-radiation. Total mesorectal excision (TME) was performed with the rectum immobilized down, and the puborectal ligament and partial levator cut to the level of the dentate line. In some well-exposed patients, it was possible to further immobilize the rectum between the external sphincter ring and the rectum inner sphincter wall. In anal approach,good exposure was attained and the cut-line was made vertically to the anal canal 2 cm below the lower edge of the tumor, and further intersphincteric immobilization was made upright. Colon or colon pouch were anastomosed to the distal anal wall.

Results: There was no peri-operative death. Thirty patients had good fecal control. Twenty-nine patients showed no evidence of recurrence or metastasis after follow-up for 12 months. Recurrence occurred in one case 1 year after operation. Another one had higher CEA 19.9 level, but without evidence of metastasis.

Conclusion: Radical resection can be attained and anal sphincter preserved by intersphincter resection which is an alternative sphincter-preserving operation.