Low Anterior Resection Syndrome (LARS) groups together bowel dysfunction symptoms which occur after rectal resection, such as fecal incontinence, urgency, frequent bowel movements and clustering of stool. For adequate surgical outcome reporting, as well as to encompass all aspects of the condition, optimal syndrome definition and clinical scoring are key. Herein, a narrative review of the literature published between 1993 and 2020 that reported on the definition of LARS and/or a LARS scoring system was undertaken.

LARS was first defined and reported by non-targeted scores, such as scores for anal incontinence and/or quality of life. Recent years have seen the emergence of scores dedicated to LARS, such as the Memorial Sloan Kettering Cancer Center Bowel Function Instrument and the Low Anterior Resection Score. These scores, and their translations, have been validated on different cohorts of patients who underwent low anterior resection.To capture all aspects of LARS, the impact of all symptoms on the patient's quality of life should be considered.