Functional outcome after intersphincteric resection of the rectum with coloanal anastomosis in low rectal cancer

Objectives. Anterior rectal resection with partial removal of the internal sphincter is an option for low rectal cancer. The objective of this study was to evaluate the functional outcome after this intersphincteric rectal resection. Methods. Anal continence was evaluated by anorectal manometry and a standardized questionnaire (Wexner Score) in 33 patients 28±15 weeks and 100±45 weeks, respectively, after intersphincteric resection. Nineteen of the 33 patients were reconstructed with a straight anastomosis; 12 received a colonic J-pouch. Results. Post-operatively, 25.8% of the patients were incontinent to solid stool and 54.8% were incontinent to liquid stool at least once a week. Mean and maximum resting tone (24±10 and 40±13 mmHg), maximum tolerable volume (77±28 ml) and rectal compliance (1.4±1.2 ml/mmHg) were reduced in anorectal manometry. Squeeze pressures remained unchanged. Only the maximum tolerable volume correlated significantly with the continence score (r=−0.45, p<0.05). The Wexner score and maximum tolerable volume were significantly better after colonic J-pouch reconstruction than after straight anastomosis (9.9±4.5 vs 13.4±4.0, p<0.05; 65±20 ml vs 100±27 ml, p<0.01). Conclusion. Intersphincteric resection of the rectum leads to impaired post-operative continence. The functional outcome is improved with a colonic J-pouch.