Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Ann Surg Oncol. 2018 Nov;25(12):3596-3603. doi: 10.1245/s10434-018-6728-7. Epub 2018 Aug 30.
Sarcopenia, characterized by loss of skeletal muscle mass, is recognized as a prognostic factor in patients with gastric cancer. However, wide variability exists in the cutoff values of muscle mass for defining sarcopenia across previous studies, and the best cutoff values to predict survival remain unknown. This study aimed to determine the optimal cutoff values for sarcopenia to predict survival in patients with advanced gastric cancer.
Patients with clinical stage II/III gastric cancer who underwent gastrectomy at Kyoto University Hospital were included in the study. The cross-sectional area of skeletal muscle at the third lumbar vertebra level was measured using preoperative computed tomography scan. The skeletal muscle index (SMI) was calculated by dividing the area by height in meters squared. Five sex-specific cutoffs of SMI, which were significantly associated with prognosis in patients with gastric and nongastric cancers, were examined as a threshold to define sarcopenia.
In the 177 eligible patients, the five cutoffs of SMI resulted in an incidence of sarcopenia between 6 (3%) and 114 (64%). The 5-year overall survival was 48% in patients with sarcopenia based on the cutoffs reported by Martin et al., compared with 68% in those without sarcopenia (p = 0.013). A multivariate regression model demonstrated that sarcopenia based on the cutoffs was significantly associated with overall survival (hazard ratio 2.00, 95% confidence interval 1.24-3.24, p = 0.005).
The cutoff values reported by Martin et al. were optimal to predict survival in patients with advanced gastric cancer.
骨骼肌减少症（Sarcopenia）的特征是骨骼肌质量的丧失，被认为是胃癌患者的预后因素。然而，在之前的研究中，用于定义骨骼肌减少症的肌肉质量的截止值存在很大差异，预测生存的最佳截止值仍不清楚。本研究旨在确定骨骼肌减少症的最佳截止值，以预测晚期胃癌患者的生存。
本研究纳入了在京都大学医院接受胃癌胃切除术的临床 II/III 期胃癌患者。使用术前计算机断层扫描测量第三腰椎水平的骨骼肌横截面积。通过将面积除以身高的平方米来计算骨骼肌指数（SMI）。检查与胃癌和非胃癌患者的预后显著相关的五个性别特异性 SMI 截止值，作为定义骨骼肌减少症的阈值。
在 177 名合格患者中，五种 SMI 截止值导致骨骼肌减少症的发生率在 6（3%）和 114（64%）之间。基于 Martin 等人报告的截止值，患有骨骼肌减少症的患者 5 年总生存率为 48%，而无骨骼肌减少症的患者为 68%（p=0.013）。多变量回归模型表明，基于截止值的骨骼肌减少症与总生存率显著相关（风险比 2.00，95%置信区间 1.24-3.24，p=0.005）。
Martin 等人报告的截止值是预测晚期胃癌患者生存的最佳选择。
