Preoperative weight loss program involving a 20‐day very low‐calorie diet for obesity before laparoscopic gastrectomy for gastric cancer

INTRODUCTION: The increased visceral fat in patients with obesity can increase the technical difficulty of surgery. This study was performed to evaluate a preoperative 20‐day very low‐calorie diet for obesity before laparoscopic gastrectomy for gastric cancer. METHODS: This prospective single‐center study involved patients with obesity who were planning to undergo laparoscopic gastrectomy for gastric cancer. Obesity was defined according to the Japanese criteria: BMI ≥25 kg/m(2) or waist circumference ≥85 cm in men and ≥90 cm in women. The patients underwent a preoperative 20‐day very low‐calorie diet and received nutritional counseling. Weight loss, body composition, visceral fat mass, and operative outcomes were evaluated. RESULTS: Thirty‐three patients were enrolled from September 2013 to August 2015. Their median age was 71 years, and 78.8% were men. Their median bodyweight and BMI were 72.3 kg (range, 53.8–82.5 kg) and 26.0 kg/m(2) (range, 23.5–31.0 kg/m(2)), respectively. The patients achieved a mean weight loss of 4.5% (95% confidence interval [CI]: 3.8–5.1), corresponding to 3.2 kg (95%CI: 2.7–3.7 kg). Body fat mass was significantly decreased by a mean of 2.5 kg (95%CI: 1.9–3.1), whereas skeletal muscle mass was unaffected (mean: −0.20 kg [95%CI: −0.55–0.15]). The visceral fat mass reduction rate was high as 16.8% (range, 11.6%–22.0%). All patients underwent laparoscopic gastrectomy as planned. Severe postoperative morbidity (Clavien–Dindo grade ≥III) was seen in only one patient (3.0%). CONCLUSION: The preoperative 20‐day very low‐calorie diet weight loss program is promising for the treatment of obesity before laparoscopic gastrectomy for gastric cancer.