P1.165. Low Preoperative Fat-Free Mass Index Predicts Anastomotic Leakage and Poor Survival in Esophageal Cancer

Abstract

Abstract Topic Esophageal Cancer: Surgical Treatment of Esophageal Cancer – long term outcomes Background Esophageal cancer is one of the most common gastrointestinal malignancies worldwide. In China, most patients are diagnosed at intermediate and advanced stages, and the treatment mainly includes neoadjuvant therapy, surgery and postoperative adjuvant therapy. Although the therapeutic effect has been greatly improved, clinical challenges still exist. Therefore, it's urgent to explore new and effective prognostic markers to identify high-risk patients at an early stage.Studies have shown that low preoperative fat-free mass index is an independent prognostic factor in several malignant tumors. However, its impact on anastomotic leakage and long-term prognosis in esophageal cancer patients remains rarely reported. Methods From January 2013 to December 2016, 411 patients who underwent radical resection for esophageal cancer were enrolled in this study. We divided patients into a low FFMI group and a high FFMI group by using the median values of FFMI for both males and females. To determine the discriminative ability of FFMI on the occurrence of anastomotic leakage after surgery, receiver operating characteristic curve (ROC) analysis was used. And then, area under curve (AUC) and 95% confidence interval (95% CI) were calculated. Kaplan Meier survival analysis was used to explore the impact of different FFMI groups on the overall survival (OS) and disease-free survival (DFS) of esophageal cancer patients, incorporating variables with significant differences (P<0.05) in the univariate Cox regression analysis into the multivariate Cox regression analysis. Results Our cohort included 245 males (59.61%) and 166 females (40.39%), with mean FFMI of 18.14±1.35 and 15.30±1.06 kg/m2, respectively. Patients were divided into low and high FFMI groups according to gender-specific median values. The overall postoperative anastomotic leakage rate was 9.98%. The low FFMI group showed significantly higher leakage rates in both males and females (males: 16.26% vs. 4.92%, P=0.004; females: 16.87% vs. 1.20%, P=0.025). Postoperative hospital stay was significantly longer in the low FFMI group for both genders (males: 15.26±9.47 vs. 12.82±6.14 days, P=0.017; females: 14.64±10.39 vs. 11.07±3.87 days, P=0.004). Kaplan–Meier analysis revealed that low FFMI was associated with poorer 5-year OS and DFS (OS: 37.4% vs. 50.2%, P=0.002; DFS: 32.0% vs. 43.9%, P=0.008). Multivariate Cox regression demonstrated that FFMI was an independent prognostic factor for OS (HR=0.73; 95%CI: 0.58–0.92; P=0.009) and DFS (HR=0.79; 95%CI: 0.64–0.98; P=0.031). Conclusion Our study found that preoperative low FFMI is a high-risk factor for increased risk of postoperative anastomotic leakage and poor survival prognosis in esophageal cancer patients. Therefore, in clinical practice, by early identification of patients with preoperative low FFMI and adopting related nutritional support and functional exercise treatments, the occurrence of poor prognosis associated with preoperative low FFMI can be reduced.