Prognostic significance of sarcopenia and skeletal muscle mass change during preoperative chemoradiotherapy in locally advanced rectal cancer

Abstract

Background: The aim of this study was to investigate the prognostic impact of sarcopenia and skeletal muscle change in rectal cancer patients who underwent preoperative chemoradiotherapy (preop-CRT). Material and methods: From April 2004 to June 2013, we identified non-metastatic rectal cancer patients who underwent preop-CRT. Sarcopenia was evaluated according to previous cut-off value by computed tomography measured before starting preop-CRT (sarcopenia_pre) and 4-6 weeks after cessation of preop-CRT (sarcopenia_post). The severe muscle loss was defined as change in muscle mass < -4.2%/100 days. The hazard ratio (HR) and 95% confidence interval (CI) of sarcopenia and muscle change were estimated using a Cox proportional hazards model adjusted for potential confounders. Results: Among 93 patients who underwent both pre and post-CRT CTs, 48 (51.6%) and 51 (54.8%) were identified as sarcopenia_pre and sarcopenia_post respectively. Twenty-three patients (24.7%) were included in the severe muscle loss group. Multivariable analysis identified sarcopenia_post (HR 2.6, 95% CI 1-6.2, p = 0.023), and severe muscle loss (HR 2.8, 95% CI 1.2-6.2, p = 0.011) along with age and ypStage as independent risk factors for overall survival. Clinical T4 stage was the only factor that can predict severe muscle loss (OR 3.4, 95% CI 1.2-9.4, p = 0.016). Conclusions: Sarcopenia identified after the completion of preop-CRT and change in muscle mass < -4.2%/100 days during preop-CRT are promising parameters to predict overall survival in patents with locally advanced rectal cancer and should be investigated more rigorously. (C) 2019 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.