结直肠癌患者腹部腰围骨骼肌的体积和密度在预后价值方面尚不清楚。本研究旨在研究腹部腰围骨骼肌的自动计算机断层扫描（CT）基于体积和密度与结直肠癌患者的生存结果之间的关联。我们回顾性评估了2010年1月至2017年10月期间接受手术治疗的474例结直肠癌患者。利用人工智能（AI）基于体组成的体积分割技术，在术前无增强CT图像上测量了腹部腰围骨骼肌指标和肌肉密度。根据骨骼肌指数（骨肌萎缩与否）和肌肉密度（肌肉脂肪变性与否）的数值及其组合（正常、单纯骨肌萎缩、单纯肌肉脂肪变性和骨肌萎缩与肌肉脂肪变性组合）对患者进行分组。采用单变量和多变量分析，包括多变量Cox比例风险回归，分析术后无病生存（DFS）和总生存（OS）。单变量分析显示，骨肌萎缩组的DFS和OS明显较非骨肌萎缩组差（log-rank检验的P值分别为0.044和0.003），肌肉脂肪变性组的DFS和OS也较非肌肉脂肪变性组差（log-rank检验的P值为＜0.001）。在多变量分析中，肌肉脂肪变性型与正常肌肉型相比，DFS的调整风险比（aHR）为1.89（95％可信区间为1.25-2.86，P = 0.003），OS的aHR为1.90（95％可信区间为1.84-3.04，P = 0.008）。与正常肌肉型相比，混合型肌肉与较差的OS相关（aHR为1.95，95％可信区间为1.08-3.54，P = 0.027）。术前利用基于AI的软件从无增强CT扫描中自动评估的体积性骨肌萎缩和肌肉脂肪变性会对结直肠癌患者的生存结果产生不利影响。Copyright © 2023韩国放射学会.

The prognostic value of the volume and density of skeletal muscles in the abdominal waist of patients with colon cancer remains unclear. This study aimed to investigate the association between the automated computed tomography (CT)-based volume and density of the muscle in the abdominal waist and survival outcomes in patients with colon cancer.We retrospectively evaluated 474 patients with colon cancer who underwent surgery with curative intent between January 2010 and October 2017. Volumetric skeletal muscle index and muscular density were measured at the abdominal waist using artificial intelligence (AI)-based volumetric segmentation of body composition on preoperative pre-contrast CT images. Patients were grouped based on their skeletal muscle index (sarcopenia vs. not) and muscular density (myosteatosis vs. not) values and combinations (normal, sarcopenia alone, myosteatosis alone, and combined sarcopenia and myosteatosis). Postsurgical disease-free survival (DFS) and overall survival (OS) were analyzed using univariable and multivariable analyses, including multivariable Cox proportional hazard regression.Univariable analysis showed that DFS and OS were significantly worse for the sarcopenia group than for the non-sarcopenia group (P = 0.044 and P = 0.003, respectively, by log-rank test) and for the myosteatosis group than for the non-myosteatosis group (P < 0.001 by log-rank test for all). In the multivariable analysis, the myosteatotic muscle type was associated with worse DFS (adjusted hazard ratio [aHR], 1.89 [95% confidence interval, 1.25-2.86]; P = 0.003) and OS (aHR, 1.90 [95% confidence interval, 1.84-3.04]; P = 0.008) than the normal muscle type. The combined muscle type showed worse OS than the normal muscle type (aHR, 1.95 [95% confidence interval, 1.08-3.54]; P = 0.027).Preoperative volumetric sarcopenia and myosteatosis, automatically assessed from pre-contrast CT scans using AI-based software, adversely affect survival outcomes in patients with colon cancer.Copyright © 2023 The Korean Society of Radiology.