Variation of body composition and its impact on survival in a global population of patients receiving multimodal treatment for esophageal cancer

e16093 Background: Growing evidence has supported a role for body composition in predicting survival in patients undergoing esophagectomy. This study seeks to define baseline variation and clinical correlates of body composition in an international cohort of patients undergoing esophagectomy for cancer. Methods: Patients who underwent esophagectomy in fourteen high-volume centers between January 2007 to December 2019 were eligible for inclusion. Skeletal muscle, visceral and subcutaneous adipose tissues within CT images, acquired at the time of diagnosis, were analyzed by a single trained assessor in accordance with a standardized protocol. Survival status was censored June 2022. Results: In total 1716 patients were recruited to this study from three global regions: North America (n = 386; 22.5%), Europe (n = 940; 54.8%) and Asia (n = 390; 22.7%). Patients were predominantly male (79.5%) and adenocarcinoma was the most common histological subtype (66.6%). Wide variation in skeletal muscle (17.1 to 83.5cm 2 ), visceral (0.2 to 170.1cm 2 ) and subcutaneous adipose tissue (0.2 to 216.8cm2) was observed. Characteristics that were significantly associated with levels of muscle and adiposity were global region, sex, age and histological subtype. Compared to adenocarcinoma, SCC was associated with significantly (p < .0001) lower levels of muscle and adiposity, a finding that was independent of global region, sex, and age using a multivariable linear regression model (p < .0001). Reduced skeletal muscle and an excess of total adiposity at the time of diagnosis was associated with 90-day mortality and worse long-term survival. A nomogram including skeletal muscle, total adiposity at diagnosis and other tumor and patient specific variables was constructed to allow convenient survival prediction. Conclusions: This is the first study to assess parameters of body composition in a global cohort of patients receiving multimodal therapy for esophageal cancer. Findings highlight important regional and disease specific variation in body composition parameters and demonstrate the clinical utility of these measurements in predicting both early and late survival after esophagectomy. Results are intended to inform future guidelines for the use of body composition assessment in routine clinical practice.