The functional results of radical rectal cancer surgery: review of the literature.

Introduction For more than the last 20 years, low anterior resection with total mesorectal excision (TME) is a gold standard for rectal cancer treatment. Oncological outcomes have improved significantly and now more and more reports of functional outcomes appear. Due to the close relationship between the rectum and pelvic nerves, bowel, bladder, and sexual function are frequently affected during TME. Methods A search for published data was performed using the MEDLINE database (from 1 January 2005 to 31 January 2015) to perform a systematic review of the studies that described anorectal, bladder, and sexual dysfunction following rectal cancer surgery. Methodological quality of the included studies was assessed using the MINORS criteria. Results Eighty-nine studies were eligible for analysis. Up to 76% of patients undergoing sphincter preserving surgery will have changes in bowel habits, the so-called "low anterior resection syndrome" (LARS). The duration of LARS varies between a few months and several years. Pre-operative radiotherapy, damage of anal sphincter and pelvic nerves, and height of the anastomosis are the risk factors for LARS. There is no evidence-based treatment available for LARS. Sexual function is more commonly affected after rectal surgery than after urinary function. The main cause of dysfunction is damage to pelvic nerves. Sexual and bladder functional outcomes in females are less well reported. Laparoscopic and robotic surgery allows better visualization of autonomic nerves and, therefore, more precise dissection and preservation. Conclusions It is important that rectal resection is standardized as much as possible, and that new functional outcome research use the same validated outcome questionnaires. This would allow for a high-quality meta-analysis.