Sphincter Preserving Operation by Coloanal Anastomosis: Long Term Survival

Purpose: Abdominoperineal resection (APR) was the conventional operation for the last 100 years, however it decreased recently for the improvement of sphincter preserving operations, especially of hand-sewn coloanal anastomosis (CAA). The aim of this study is to evaluate oncological results for the CAA. Methods: From January 1992 to August 2000, 107 consecutive patients with rectal cancer within 7 cm from anal verge who underwent a curative resection were evaluated retrospectively by operations (APR, CAA, and stapled low anterior resection, LAR). No temporary stoma was made for CAA and LAR. Results: The mean age is 57.4 and the distance from the anal verge was 4.12 cm (1.55) for 65 males and 4.13 cm (1.67) for 42 females (p>0.05). The age, gender, tumor location, size, resection margin, and stage were not statistically significant according to the operations. The CAA increased from 8% (early) to 64% (late), and the APR decreased from 59% (early) to 16% (late). The 5 year survival rate was 70.1% (84.3% for Dukes B and 40.8% for Dukes C). Survivals were not statistically significant according to the type of operation. The local recurrence rate was 7.4% (13.8% for stapled low anterior resection, 7.0% for APR, and 2.8% for CAA). Of the patients with a CAA, 54% had received preoperative radiation therapy (4555 Gy). In the late period, tumors located within 5 cm from the anal verge with fat or perirectal lymph nodes involved received preoperative radiation, and the sphincter-preserving rate was 80%. Conclusions: CAA is an effective technique, with a safe oncologic result, for sphincter preservation in very low rectal cancer.