Mean Muscle Attenuation within Paraspinal Muscle as a Determinant of Survival in Patients with Gastric Cancer Undergoing Gastrectomy

Abstract

Background: This study aimed to evaluate the prognostic potential of skeletal muscle mass and muscle quality at the level of the third lumbar vertebra (L3) using computerized tomography (CT) images in patients with stage I–III gastric cancer (GC) who underwent curative gastric resection.Methods: Patients with stage I–III GC who underwent curative gastric resection between October 2006 and June 2014 were enrolled in this study. Demographic and clinical parameters were collected and analyzed. The muscle-related parameters (MRPs), such as the area of total abdominal wall musculature (SMA), area of paraspinal muscle (PMA), mean muscle attenuation (MA) within the total abdominal wall musculature (SMMA), and MA in the paraspinal muscle (PMMA), were measured at the L3 level using CT images. The Kaplan-Meier curve analyses and Cox proportional hazards model were applied to the MRPs, demographic, and clinical parameters to explore the overall survival (OS) and disease-free survival (DFS).Results: Overall, data from 339 patients (233 men and 116 women) were analyzed in this study. In the multivariate Cox model, the elderly (hazard ratio [HR] 2.08, 95% confidence interval [CI] 1.30–3.32, p=0.002), total gastrectomy (HR 2.14, 95% CI 1.32–3.48, p=0.002), stage (HR 3.41, 95% CI 2.10–5.54, p<0.001), perineural invasion (HR 2.01, 95% CI 1.02–3.93, p=0.042), prognostic nutritional index (PNI) (HR 0.91, 95% CI 0.88–0.95, p<0.001), and PMMA (HR 2.36, 95% CI 1.47–3.78), p<0.001) were prognostic factors for OS. Similarly, the elderly (HR 1.68, 95% CI 1.09–2.59, p=0.018), total gastrectomy (HR 2.16, 95% CI 1.37–3.38, p<0.001, stage (HR 4.16, 95% CI 2.64–6.54, p<0.001), PNI (HR 0.91, 95% CI 0.87–0.94, p<0.001), and PMMA (HR 2.22, 95% CI 1.42–3.47, p<0.001) were prognostic factors for DFS.Conclusions: PMMA is suggested as a determinant of OS and DFS in stage I through III GC patients who underwent gastrectomy. Because PMMA is a newly characterized parameter in GC, external validation before clinical applications is a prerequisite.