Impact of nutritional status and body composition on postoperative outcomes after pelvic exenteration for locally advanced and locally recurrent rectal cancer

BACKGROUND: Pelvic exenteration for locally advanced rectal cancer (LARC) and locally recurrent (LRRC) rectal cancer provides radical resection and local control, but is associated with considerable morbidity. The aim of this study was to determine risk factors, including nutritional status and body composition, for postoperative morbidity and survival after pelvic exenteration in patients with LARC or LRRC. METHODS: Patients with LARC or LRRC who underwent total or posterior pelvic exenteration in a tertiary referral centre from 2003 to 2018 were analysed retrospectively. Nutritional status was assessed using the Malnutrition Universal Screening Tool (MUST). Body composition was estimated using standard-of-care preoperative CT of the abdomen. Logistic regression analyses were performed to identify risk factors for complications with a Clavien–Dindo grade of III or higher. Risk factors for impaired overall survival were calculated using Cox proportional hazards analysis. RESULTS: In total, 227 patients who underwent total (111) or posterior (116) pelvic exenteration were analysed. Major complications (Clavien–Dindo grade at least III) occurred in 82 patients (36.1 per cent). High risk of malnutrition (MUST score 2 or higher) was the only risk factor for major complications (odds ratio 3.99, 95 per cent c.i. 1.76 to 9.02) in multivariable analysis. Mean follow-up was 44.6 months. LRRC (hazard ratio (HR) 1.61, 95 per cent c.i. 1.04 to 2.48) and lymphovascular invasion (HR 2.20, 1.38 to 3.51) were independent risk factors for impaired overall survival. CONCLUSION: A high risk of malnutrition according to the MUST is a strong risk factor for major complications in patients with LARC or LRRC undergoing exenteration surgery.