肌间脂肪组织作为结直肠癌总生存期的预后生物标志物
本回顾性队列研究纳入1080例I-III期结直肠癌术后患者，基于L3水平CT测量肌间脂肪组织（IMAT）面积与密度。按性别特异性阈值将患者分为IMAT组合组，发现低IMAT指数和低IMAT密度与更好的总生存期相关。IMAT模型是独立预后因素，其预测性能优于单独骨骼肌指标。
要点
- L3水平CT测量的IMAT指数和密度是结直肠癌患者的独立预后因素，低值提示更好总生存期。
- IMAT组合模型预测总生存期的C指数高于SMI和SMD单独使用，可用于个体化治疗规划。
- 阅片时可关注L3层面肌间脂肪面积与密度，结合性别特异性阈值辅助预后分层。
核心结论
- IMAT模型是结直肠癌患者总生存期的独立预后因素，纳入该模型可提升预后预测准确性并支持个体化治疗规划。
研究设计与样本
- 单中心回顾性队列研究，纳入2005年至2014年间接受手术的I-III期结直肠癌患者1080例，男性占59.4%。
- 采用L3水平CT图像测量骨骼肌面积、IMAT面积和IMAT密度，参考标准为总生存期随访数据。
关键影像表现/征象
- L3水平CT上较低的IMAT指数（IMAT面积/身高²）和较低的IMAT密度与更好的总生存期相关。
- IMAT组合组G2-G4的总生存期显著优于G1组。
诊断标准与关键数值
- 使用X-tile程序确定IMAT指数和IMAT密度的性别特异性阈值，并据此将患者分为G1、G2、G3、G4四组。
- IMAT模型（G1 vs G2-G4）预测总生存期的C指数为0.629，高于SMI单独的0.579，bootstrap平均差值0.050，95%CI：0.021-0.091。
- IMAT模型预测总生存期的C指数为0.617，高于SMD单独的0.590，bootstrap平均差值0.027，95%CI：0.009-0.052。
临床应用与阅片要点
- 日常阅片中可在L3水平CT图像上测量IMAT面积与密度，结合性别特异性阈值对结直肠癌患者进行预后分层。
- IMAT组合分组较单一骨骼肌指标更能反映预后，报告时可提及IMAT模型相关信息。
- 注意IMAT预后价值依赖于解剖部位选择和CT图像分析方法，需规范测量流程。
局限性
- 本研究为单中心回顾性队列研究，可能存在选择偏倚和混杂因素。
- IMAT相关参数的预后价值依赖于CT成像解剖部位选择和分析技术，结果外推需谨慎。
以上解读依据论文摘要（全文未开放获取或许可不允许翻译转载）。
英文原文（摘要）· 点击展开
BACKGROUND: The prognostic value of intermuscular adipose tissue (IMAT) in patients with colorectal cancer (CRC) depends on both the anatomical site selected for CT imaging and the analytical technique employed. This study assessed the clinical significance of IMAT-related parameters in patients with CRC.
METHODS: This retrospective cohort study included stage I-III CRC patients who underwent surgery at a single tertiary center between 2005 and 2014. CT scans at the L3 level measured skeletal muscle and IMAT area and radiodensity. Sex-specific cutoffs for IMAT index (IMAI: IMAT area/height2) and IMAT radiodensity (IMAD) were defined using the X-tile program. Patients were further categorized into IMAT-combined groups (G1, G2, G3, and G4) according to the cutoff values of IMAI and IMAD. Survival was analyzed using Kaplan-Meier curves, log-rank tests, and Cox regression. Prognostic accuracy was evaluated with the concordance index (C-index).
RESULTS: Among 1080 patients (59.4% male), lower IMAI and IMAD correlated with better overall survival (OS). IMAT-combined groups were independent prognostic factors, with G2-G4 showing significantly better OS than G1. Patients were reclassified into two groups (G1 vs. G2-G4), termed the "IMAT model." The C-index demonstrated that incorporating the IMAT model yielded superior predictive performance compared to SMI alone (0.629 vs. 0.579; bootstrap mean difference = 0.050, 95% CI: 0.021-0.091) and SMD alone (0.617 vs. 0.590; bootstrap mean difference = 0.027, 95% CI: 0.009-0.052).
CONCLUSIONS: The IMAT model is a significant independent prognostic factor for patients with CRC. Its use may enhance prognostic accuracy and support personalized treatment planning.
引用
- Kim, Lee, Lee, et al. Intermuscular adipose tissue as a prognostic biomarker for overall survival in colorectal cancer. Eur J Radiol. 2026. PMID: 42247994. doi:10.1016/j.ejrad.2026.112966
供执业医师工作参考，不替代临床判断；数值与分级以指南原文为准。