Impact Of Preoperative And Postoperative Body Mass Index On Disease-Free Survival After Resection For Gastric Cancer

To investigate the associations between preoperative and postoperative body mass index (BMI) and disease-free survival (DFS) in patients with gastric cancer. Methods: A total of 434 patients who underwent a curative (RO) resection for gastric cancer between 2011 and 2013 were retrospectively studied. We recorded preoperative BMI, BMI at 1 month after surgery and BMI at 6 months after surgery. All patients were divided into 3 groups according to their BMI: low BMI group (< 18.5 kg/m(2)), normal BMI group (18.5-25 kg/m(2)), and high BMI group (>= 25 kg/m(2)). Clinical-pathological characteristics, oncologic outcomes, and DFS were collected and compared between the 3 groups. To analyze the effects of changes in BMI from before surgery to 6 months after surgery on DFS, patients were stratified into a stable BMI, increased BMI, and decreased BMI group. DFS was compared between the 3 groups. Results: Regarding preoperative BMI, the 2-year DFS rate was 70.3% in low BMI group, 71.5% in normal BMI group, and 68.8% in high BMI group (P=0.904). No significant differences were observed in DFS according to postoperative BMI. Using changes in BMI to predict DFS, the 2-year DFS rate was 72.2% in the stable BMI group, 91.7% in the increased BMI group, and 64.8% in the decreased BMI group (P=0.149). In a Cox proportional hazards model, a high BMI before surgery, compared to normal BMI, was associated with a lower DFS (hazard ratio 2.64; 95% confidence interval, 1.02-6.84, P=0.045). However, postoperative BMI and BMI change status were also not associated with DFS. Conclusion: Before surgery, normal BMI significantly predicted the higher DFS of patients with gastric cancer compared with the high BMI. However, postoperative BMI and changes in BMI were not independent prognostic factors of DFS.