Postoperative Changes in Body Composition Predict Long-Term Prognosis in Patients with Gastric Cancer

Abstract

Background: Postoperative changes in body composition (BC) have not been clearly defined. The aim of this study was to clarify the impact of postoperative comprehensive changes in BC on long-term prognosis in gastric cancer (GC) patients. Methods: A total of 366 GC patients who underwent radical gastrectomy were included. Postoperative changes in skeletal muscle volume, body fat volume, and skeletal muscle density were investigated at six months postoperatively using computed tomography and evaluated their association with long-term survival. Results: Patients with decreased muscle volume, decreased fat volume, and increased muscle density had a poor prognosis, respectively. When the risk scores based on these three BC parameters were applied, patients were classified from score 0 to 4, with survival rate declining as the scores improved: score 0, interim 5-year overall survival 94%; score 1, 82%; score 2, 73%; score 3, 56%; and score 4, 20%. BC change (score > 2) was an independent poor prognosticator (HR, 3.086; p < 0.001). Preoperative myosteatosis, high Charlson comorbidity, and total gastrectomy were identified as significant independent risk factors for BC change. Conclusions: Each of postoperative skeletal muscle loss, body fat loss, and muscle hyperdensity negatively affected prognosis of GC patients after surgery, and the BC risk scoring assessment well predicted the prognosis of postoperative patients with GC.