Anorectal function after anterior resection with side-to-side anastomosis for carcinoma of the rectum

The aim of this study is to demonstrate whether anorectal function after anterior resection with side-to-side anastomosis results in better clinical outcomes than end-to-end anastomosis in patients with carcinoma of the upper half of the rectum.

Anorectal function was studied in two groups of patients who had anterior resection, those with end-to-end anastomosis (Group E; n = 11) and those with side-to-side anastomosis (Group S; n = 11). Eight control subjects who had sigmoid colectomy for carcinoma were also studied. Each patient underwent manometric study and was questioned about clinical bowel symptoms before the operation and 3, 6, and 12 months postoperatively.

The median length of residual rectum in both Group S and Group E was 7 cm. No significant difference was observed in maximum anal resting pressure and maximum squeeze pressure between the groups before and after operation. Maximum tolerable volume in Group S was significantly higher than that in Group E and was close to that in the control group at each postoperative interval. Median volumes in Group S were 200 ml (3 months), 220 ml (6 months), and 220 ml (12 months). Median volumes in Group E were 140 ml (3 months), 150 ml (6 months), and 175 ml (12 months). Bowel frequency per 24 hours at three and six months postoperatively was significantly greater in Group E than in Group S or the control group. Median frequency in Group E was four times (3 months) and three times (6 months) per 24 hours. Median frequency in both Group S and the control group was two times (3 months) and two times (6 months) per 24 hours. Postoperative urgency of defecation was not found in Group S, significantly less frequent than in Group E at three months.

Side-to-side anastomosis may lead to a better clinical outcome than end-to-end anastomosis for carcinoma of the upper half of the rectum in the adaptation phase.