Usefulness of Anorectal Manometry for Diagnosing Continence Problems After a Low Anterior Resection

Purpose: For several decades, the low anterior resection (LAR) with total mesorectal excision (TME) has been the gold standard for treating patients with rectal cancer. Up to 90% of patients undergoing sphincter-preserving surgery will have changes in bowel habits, so-called 'anterior resection syndrome.' This study examined patients' continence after a LAR for the treatment of rectal cancer. Methods: This prospective study was performed between September 2014 and August 2015 at the National Cancer Institute and included 30 patients who underwent anorectal manometry preoperatively and at 3 and 4 months after a LAR, but 10 were excluded from further evaluation for various reasons. Wexner score was recorded preoperatively and 4 months after LAR (1 month after ileostomy repair). Results: Postoperatively, 70% of patients complained of some degree of soiling (incontinence to liquid stool), and 30% experienced urgent defecation. Four months after surgery, these symptoms had somewhat abated. The anal resting pressure and the maximum squeezing pressure did not change significantly. Rectal capacity and compliance were reduced in all patients. The majority of patients demonstrated manometric anorectal changes and clinical anorectal function disorders during the first 4 months after surgery. The Wexner scores and the manometric findings showed no correlation. Conclusion: Many patients undergoing a LAR with TME for the treatment of rectal cancer experience some degree of incontinence postoperatively. Anorectal manometry may be used as an additional tool for evaluating problems with continence after a LAR. No correlation between the Wexner score and the manometric findings was observed.