EWGSOP2 versus EWGSOP1 for sarcopenia to predict prognosis in patients with gastric cancer after radical gastrectomy: Analysis from a large-scale prospective study

Background In 2010, the European Working Group on Sarcopenia in Older People (EWGSOP) reached a consensus on sarcopenia (EWGSOP1). In 2018, the EWGSOP met again (EWGSOP2) to update original definition of sarcopenia. This study aimed to investigate the association of sarcopenia and survival and compare the prognostic effects of sarcopenia as defined by EWGSOP1 and EWGSOP2 after gastrectomy. Methods We conducted a prospective study including patients who underwent curative gastrectomy for gastric cancer from August 2014 to February 2018. The sarcopenia elements, including skeletal muscle index, muscle attenuation, handgrip strength, and gait speed were measured before surgery. Patients were followed up after gastrectomy to gain the actual clinical outcomes. Results The prevalence of sarcopenia was 17.0% and 18.9% according to the EWGSOP1 and EWGSOP2 respectively. Sarcopenia was independent risk factor for postoperative complications. Compared with EWGSOP1-sarcopenia, EWGSOP2-sarcopenia and had a higher odds ratio (OR) (2.453 vs. 1.550) in multivariate model. Area under the ROC curve of model including EWGSOP2-sarcopenia was larger than that of the model including EWGSOP1-sarcopenia (AUC 0.653 vs. 0.634, P = 0.021). For both of EWGSOP1 and EWGSOP2, sarcopenia was an independent risk factor for overall survival (OS) and disease-free survival (DFS), but EWGSOP2-sarcopenia seemed to have a higher hazard ratio (OS, 1.667 vs. 1.449; DFS, 1.603 vs. 1.563). In addition, severe sarcopenia, as defined by either EWGSOP2 or EWGSOP1, had a strong predictive power (OR 4.909 vs. 3.827) for postoperative complications. Both versions of severe sarcopenia were significantly predictive of OS and DFS in Cox analysis. Conclusion Sarcopenia at uniform diagnosis standard was an independent risk factor for survival in patients undergoing radical gastrectomy for gastric cancer. Sarcopenia defined by EWGSOP2 criteria better predicts clinical outcomes than that defined by EWGSOP1 criteria in patients with gastric cancer after gastrectomy.