Clinical Significance of Paraspinal Muscle Parameters as a prognostic factor for survival in Gastric Cancer Patients who underwent Curative Surgical Resection

Background: The quantitative and qualitative skeletal muscle parameters have been proposed to predict the outcome of patients with gastric cancer. However, the evidence for their association with long-term survival is still conflicting. This study aimed to investigate the effect of paraspinal muscle parameters on overall survival (OS) and disease-free survival (DFS) in patients with gastric cancer who underwent curative resection. Methods: Patients with stages I or II gastric cancer who underwent curative resection between October 2006 and June 2016 were identified from electrical medical records. Paraspinal muscle area and attenuation were measured at the level of the third lumbar vertebra using computerized tomography images. For the analysis of OS and DFS, proportional hazards model was used, incorporating demographic, pathologic, laboratory, and radiologic variables. Results: This study enrolled 296 patients (192 men and 104 women). In the multivariate proportional hazards model, total gastrectomy (hazard ratio [HR], 2.65; 95% Confidence interval [CI], 1.36-5.19; p = 0.0044), neutrophil-lymphocyte ratio (NLR) (HR, 1.27; 95% CI, 1.06-1.51; p = 0.0081), serum albumin level (HR, 0.16; 95% CI, 0.07-0.39; p < 0.0001), paraspinal muscle area adjusted for body surface area (PMA(BSA)) (HR, 3.06; 95% CI, 1.65-5.67; p = 0.0004), and mean attenuation in paraspinal muscle (PMMA) (HR, 3.38; 95% CI, 1.75-6.53; p = 0.0003) were prognostic factors for OS. Similarly, total gastrectomy (HR, 2.11; 95% CI, 1.10-4.06; p = 0.0243), NLR (HR, 1.25; 95% CI, 1.06-1.48; p = 0.0071), serum albumin level (HR, 0.22; 95% CI, 0.10-0.51; p = 0.0035), PMA(BSA )(HR, 2.42; 95% CI, 1.34-4.37; p = 0.0035), and PMMA (HR, 3.19; 95% CI, 1.71-5.93; p = 0.0003) were prognostic factors for DFS. Conclusions: The pretreatment paraspinal muscle parameters such as PMA(BSA) and PMMA along with total gastrectomy, NLR, and serum albumin level could predict OS and DFS in patients with stages I or II gastric cancer who underwent curative surgical resection. Because PMA(BSA) and PMMA are newly characterized parameters in gastric cancer, the relationship with the survival of these parameters requires further validation in further studies before they are subjected to clinical applications.