Preoperative Muscle-Adipose Index: A New Prognostic Factor for Gastric Cancer.

ABSTRACT

BACKGROUND: Studies have shown that traditional nutrition indicators and body composition indicators are closely related to prognosis after radical gastric cancer (GC) surgery. However, the effect of the combined muscle and adipose composite on the prognosis of GC has not been reported. METHODS: The clinicopathological data of 514 patients with GC were retrospectively analyzed. The skeletal muscle adipose tissue were measured by preoperative CT images to obtain the muscle index and adipose index. X-tile software was used to determine the diagnostic threshold of muscle-adipose imbalance. RESULTS: The 5-year OS and RFS of the muscle-adipose imbalanced group were significantly worse than those of the balanced group. Multivariate analysis showed that muscle-adipose imbalance and the CONUT score were independent prognostic factors of OS and RFS (p < 0.05). The nuclear density curve showed that the recurrence risk of the muscle-adipose imbalanced group was higher than that of the balanced group, whereas the nuclear density curve of the CONUT score was confounded. Incorporating the muscle-adipose index into cTNM has the same prognostic performance as the pTNM staging system. Chemotherapy-benefit analysis showed that stage II/III patients in the muscle-adipose balanced group could benefit from adjuvant chemotherapy. CONCLUSIONS: The preoperative muscle-adipose index discovered for the first time is a new independent prognostic factor that affects the prognosis with GC. In addition, the preoperative muscle-adipose index is better than traditional nutrition and body composition indicators in terms of the prognostic evaluation of GC patients and the predictive value of recurrence risk.