Incidence and risk factors of bowel dysfunction after minimally invasive rectal cancer surgery and discrepancies between the Wexner score and the low anterior resection syndrome (LARS) score

Bowel dysfunction after sphincter-preserving-surgery (SPS) impacts quality of life. The Wexner score (WS) and the low anterior resection syndrome (LARS) score (LS) are instruments for assessing postoperative bowel dysfunction. We analyzed the incidence of and risk factors for each symptom and examined the discrepancies between the two scores.

A total of 142 patients with rectal cancer, who underwent minimally invasive SPS between May, 2018 and July, 2019, were included. A questionnaire survey using the two scores was given to the patients 2 years after SPS.

Tumor location and preoperative radiotherapy were independent risk factors for major LARS. Intersphincteric resection with a hand-sewn anastomosis (HSA) was an independent risk factor for high WS. Among the patients who underwent HSA, 82% experienced incontinence for liquid stools, needed to wear pads, and suffered lifestyle alterations. Of the 35 patients with minor LARS, only 1 had a high WS, and 80.0% reported no lifestyle alterations. Among the 75 patients with major LARS, 58.7% had a low WS and 21.3% reported no lifestyle alterations.

The results of this study provide practical data to help patients understand potential bowel dysfunction after SPS. The discrepancies between the WS and LS were clarified, and further efforts are required to utilize these scores in clinical practice.