Low anterior resection syndrome score: development and validation of a symptom-based scoring system for bowel dysfunction after low anterior resection for rectal cancer.

OBJECTIVE The aim of this study was to develop and validate a scoring system for bowel dysfunction after low anterior resection (LAR) for rectal cancer, on the basis of symptoms and impact on quality of life (QoL). BACKGROUND LAR for rectal cancer often results in severe bowel dysfunction (LAR syndrome [LARS]) with incontinence, urgency, and frequent bowel movements. Several studies have investigated functional outcome, but the terminology is inconsistent hereby complicating comparison of results. METHODS Questionnaires regarding bowel function was sent to all 1143 LAR patients eligible for inclusion identified in the national Colorectal Cancer Database. Associations between items and QoL were computed by binomial regression analyses. The important items were selected and regression analysis was performed to find the adjusted risk ratios. Individual score values were designated items to form the LARS score, which was divided into "no LARS," "minor LARS," and "major LARS." Validity was tested by receiver operating characteristic (ROC) curve and Spearman's rank correlation and discriminant validity was tested by Student t tests. RESULTS A total of 961 patients returned completed questionnaires. The 5 most important items were "incontinence for flatus," "incontinence for liquid stools," "frequency," "clustering," and "urgency." The range (0-42) was divided into 0 to 20 (no LARS), 21 to 29 (minor LARS), and 30 to 42 (major LARS). The score showed good correlation and a high sensitivity (72.54%) and specificity (82.52%) for major LARS. Discriminant validity showed significant differences between groups with and without radiotherapy (P < 0.0001), tumor height more or less than 5 cm (P < 0.0001), and total mesorectal excision/partial mesorectal excision (P = 0.0163). CONCLUSIONS We have constructed a valid and reliable LARS score correlated to QoL--a simple tool for quick clinical evaluation of the severity of LARS.