Preoperative nutritional risk index and postoperative one-year skeletal muscle loss can predict the prognosis of patients with gastric cancer: a registry based study

Abstract

Background: Patients with gastric cancer have increased nutritional risk and experience a significant skeletal muscle loss after surgery. We aimed to determine whether muscle loss during the first postoperative year and nutritional status are indicators for predicting prognosis. Methods: From a gastric cancer registry, a total of 958 patients who received curative gastrectomy followed by chemotherapy for stage 2 and 3 gastric cancer and survived longer than 1 year were investigated. Clinical and laboratory data were collected. Skeletal muscle index (SMI) was assessed based on the muscle area at the L3 level on abdominal computed tomography. Results: Preoperative nutritional risk index (NRI) and postoperative decrement of SMI (dSMI) were significantly associated with overall survival (hazards ratio: 0.972 [95% CI: 0.958-0.986] and 1.058 [95% CI: 1.033-1.085], respectively) in a multivariate Cox regression analysis. Recurrence, tumor stage, comorbidity, and the preoperative muscle and subcutaneous fat area were also significant prognostic indicators. Kaplan-Meier analyses exhibited that patients with higher NRI had a significantly longer survival than those with lower NRI (3-year overall survival: 84.6% vs. 72.9%, P < 0.001). In addition, a significantly better prognosis was observed in a patient group with less decrease of SMI (3-year overall survival: 85.6% vs. 74.5%, P = 0.009). A logistic regression analysis demonstrated that the performance of preoperative NRI and dSMI in mortality prediction was quite significant (AUC: 0.63, P < 0.001) and the combination of clinical factors enhanced the predictive accuracy to the AUC of 0.90 (P < 0.001). This prognostic relevance of NRI and dSMI was maintained in patients experiencing tumor recurrence. Conclusions: Skeletal muscle loss during the first postoperative year and preoperative NRI are predictors of overall survival in stage 2 or 3 gastric cancer patients regardless of relapse. Our results support the potential importance of exercise and nutritional support along with standard treatment.