Anterior resection syndrome: What should we tell practitioners and patients in 2018?

Multidisciplinary management of infra-peritoneal rectal cancer has pushed back the frontiers of sphincter preservation, without impairment of carcinological outcome. However, functional intestinal sequelae, grouping together several symptoms known under the name of anterior resection syndrome (ARS), have emerged and become an increasingly frequent concern for both patients and physicians. The pathophysiology is complex: ARS is a combination in various degrees of stool frequency, incontinence for flatus and/or stools, urgency, and disorders in discrimination and evacuation. The "Low Anterior Resection Score" (LARS), validated in 2012, is currently used to evaluate the severity of ARS and its impact on quality of life. While ARS can show improvement over the first two years, symptoms persist for longer than two years in nearly 60% of patients and in half of these patients, ARS is considered severe. The most frequently reported independent risk factors of severe ARS include neo-adjuvant radiation therapy, the extent of resection (total mesorectal excision that includes inter-sphincteric resection), absence of colonic pouch and anastomotic leak. In the absence of surgical complications and/or local recurrence, physicians can draw from a wide therapeutic armamentarium in order to improve the functional outcome of patients, including diet and lifestyle modifications, gut motility regulators, multimodal rehabilitation (biofeedback, electro-stimulation) and sacral nerve modulation. Permanent colostomy is an alternative of last resort, proposed only when all other solutions fail. A better understanding of the natural history of ARS, its risk factors as well as the array of therapeutic alternatives should provide better patient information and optimize management.