Impact of Body Mass Index and Sarcopenia on Short- and Long-Term Outcomes After Esophageal Cancer Surgery: An Observational Study.

BACKGROUND: The effects of specific body mass index (BMI) category and sarcopenia within each BMI category on outcomes in patients undergoing esophageal surgery with esophageal squamous cell carcinoma have not been thoroughly examined. METHODS: This study included 1141 patients. Sarcopenia was determined with a total psoas muscle cross-sectional area at the level of the third lumbar vertebra in computed tomography. The outcomes were long-term survival, including overall survival (OS) and recurrence-free survival (RFS), and postoperative complications. RESULTS: The overweight and no sarcopenia group was considered as the reference. After adjusting covariates, the underweight and the normal weight and sarcopenia groups both showed worse OS (underweight group: hazard ratio [HR] 2.04, 95% confidence interval [CI] 1.33-3.13, p = 0.001; normal weight and sarcopenia group: HR 1.93, 95% CI 1.39-2.69, p < 0.001) and worse RFS (underweight group: HR 1.78, 95% CI 1.19-2.67, p = 0.005; normal weight and sarcopenia group: HR 1.70, 95% CI 1.25-2.30, p = 0.001). In addition, the underweight group (odds ratio [OR] 4.74, 95% CI 2.05-10.96, p < 0.001), the normal weight and sarcopenia group (OR 3.26, 95% CI 1.60-6.62, p = 0.001), the overweight and sarcopenia group (OR 2.54, 95% CI 1.14-5.68, p = 0.023), and the obese and no sarcopenia group (OR 2.44, 95% CI 1.14-5.22, p = 0.021) were at significantly higher risk of postoperative 30-day composite complications. CONCLUSIONS: Compared with the overweight and no sarcopenia group, the underweight and the normal weight and sarcopenia groups were associated with worse short- and long-term outcomes.