Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China.
J Cachexia Sarcopenia Muscle. 2024 Apr;15(2):702-717. doi: 10.1002/jcsm.13424. Epub 2024 Jan 31.
The body composition of patients with rectal cancer potentially affects postoperative outcomes. This study explored the correlations between skeletal muscle and adipose tissue quantified by computed tomography (CT) with postoperative complications and long-term prognosis in patients with rectal cancer after surgical resection.
This retrospective cohort study included patients with rectal cancer who underwent surgical resection at the Wuhan Union Hospital between 2014 and 2018. CT images within 3 months prior to the surgery were used to quantify the indices of skeletal muscle and adipose tissue at the levels of the third lumbar vertebra (L3) and umbilicus. Optimal cut-off values for each index were defined separately for males and females. Associations between body composition and postoperative complications, overall survival (OS), and disease-free survival (DFS) were evaluated using logistic and Cox proportional hazards models.
We included 415 patients (240 males and 175 females; mean age: 57.8 ± 10.5 years). At the L3 level, a high skeletal muscle density (SMD; hazard ratio [HR]: 0.357, 95% confidence interval [CI]: 0.191-0.665, P = 0.001; HR: 0.571, 95% CI: 0.329-0.993, P = 0.047) and a high skeletal muscle index (SMI; HR: 0.435, 95% CI 0.254-0.747, P = 0.003; HR: 0.568, 95% CI: 0.359-0.897, P = 0.015) were independent prognostic factors for better OS and DFS. At the umbilical level, a large intermuscular fat area (IMFA; HR: 1.904, 95% CI: 1.068-3.395, P = 0.029; HR: 2.064, 95% CI: 1.299-3.280, P = 0.002) was an independent predictive factor for worse OS and DFS, and a high SMI (HR: 0.261, 95% CI: 0.132-0.517, P < 0.001; HR: 0.595, 95% CI: 0.387-0.913, P = 0.018) was an independent prognostic factor for better OS and DFS. The models combining body composition and clinical indicators had good predictive abilities for OS. The receiver operating characteristic areas under the curve were 0.848 and 0.860 at the L3 and umbilical levels, respectively (both P < 0.05).
No correlations existed between CT-quantified body composition parameters and postoperative complications. However, a high SMD and high SMI were significantly associated with longer OS and DFS at the L3 level, whereas a large IMFA and low SMI were associated with worse OS and DFS at the umbilical level. Combining CT-quantified body composition and clinical indicators could help physicians predict the prognosis of patients with rectal cancer after surgery.
直肠癌患者的身体成分可能会影响术后结果。本研究探讨了通过计算机断层扫描（CT）定量的骨骼肌和脂肪组织与直肠癌患者术后并发症和长期预后的相关性。
本回顾性队列研究纳入了 2014 年至 2018 年期间在武汉协和医院接受手术切除的直肠癌患者。使用手术前 3 个月内的 CT 图像定量第三腰椎（L3）和脐水平的骨骼肌和脂肪组织指数。分别为男性和女性定义每个指数的最佳截断值。使用逻辑和 Cox 比例风险模型评估身体成分与术后并发症、总生存期（OS）和无病生存期（DFS）之间的关联。
我们纳入了 415 名患者（240 名男性和 175 名女性；平均年龄：57.8±10.5 岁）。在 L3 水平，高骨骼肌密度（SMD；风险比 [HR]：0.357，95%置信区间 [CI]：0.191-0.665，P=0.001；HR：0.571，95%CI：0.329-0.993，P=0.047）和高骨骼肌指数（SMI；HR：0.435，95%CI 0.254-0.747，P=0.003；HR：0.568，95%CI：0.359-0.897，P=0.015）是 OS 和 DFS 较好的独立预后因素。在脐水平，较大的肌间脂肪面积（IMFA；HR：1.904，95%CI：1.068-3.395，P=0.029；HR：2.064，95%CI：1.299-3.280，P=0.002）是 OS 和 DFS 较差的独立预测因素，而高 SMI（HR：0.261，95%CI：0.132-0.517，P<0.001；HR：0.595，95%CI：0.387-0.913，P=0.018）是 OS 和 DFS 较好的独立预后因素。结合身体成分和临床指标的模型对 OS 具有良好的预测能力。L3 和脐水平的曲线下面积分别为 0.848 和 0.860（均 P<0.05）。
CT 定量的身体成分参数与术后并发症之间没有相关性。然而，在 L3 水平，高 SMD 和高 SMI 与较长的 OS 和 DFS 显著相关，而较大的 IMFA 和较低的 SMI 与较差的 OS 和 DFS 相关。结合 CT 定量的身体成分和临床指标可以帮助医生预测直肠癌患者手术后的预后。
