Risk Factors for Fecal Incontinence After Intersphincteric Resection for Rectal Cancer

BACKGROUND: Restoration of bowel continuity is a major goal after surgical treatment of rectal cancer. Intersphincteric resection allows sphincter preservation in low rectal cancer but may have poor functional results, including frequent bowel movements, urgency, and incontinence. OBJECTIVE: This study aimed to evaluate long-term functional outcome after intersphincteric resection to identify factors predictive of good continence. DESIGN: Descriptive observational study. SETTING: Follow-up of surgery in tertiary care university hospital. PATIENTS: Eligible patients were without recurrence 1 year or more after surgery for low rectal cancer. INTERVENTION: Intersphincteric resection. MAIN OUTCOME MEASURES: Bowel function was assessed with a standardized questionnaire sent to patients. Functional outcome was considered as good if the Wexner score was 10 or less. Univariable and multivariable regression analyses were used to evaluate impact of age, gender, body mass index, tumor stage, tumor location, distance of the tumor from the anal verge and from the anal ring, type of surgery, colonic pouch, height of the anastomosis, pelvic sepsis, and preoperative radiotherapy on functional outcome. RESULTS: Of 125 eligible patients, 101 responded to the questionnaire. Median follow-up was 51 (range, 13-167) months. In multivariate analyses, the only independent predictors of good continence were distance of the tumor greater than 1 cm from the anal ring (OR, 5.88; 95% CI, 1.75-19.80; P = .004) and anastomoses higher than 2 cm above the anal verge (OR, 6.59; 95% CI, 1.12-38.67; P = .037). LIMITATIONS: The study is limited by its retrospective, observational design and potential bias due to possible differences between those who responded to the questionnaire and those who did not. CONCLUSIONS: Patient characteristics do not appear to influence functional outcome at long-term follow-up after intersphincteric resection. The risk of fecal incontinence depends mainly on tumor level and height of the anastomosis.