L3水平CT横截面机体组成改变对结直肠癌病人生存预后的价值分析

Role of CT-derived body composition measurement at the L3 vertebra level for prognosis and survival of colorectal cancer patients

目的:探究CT测算身体成分变化对结直肠癌并行放化疗病人预后的评估价值。方法:对142例结直肠癌(CRC)病人进行回顾性分析。采集病人治疗前后的腹部CT第三腰椎层面的图像,得出骨骼肌指数(SMI),内脏脂肪指数(VATI)及皮下脂肪指数(SATI)。参照文献报道中的截断值定义肌少症,使用Cox回归模型分析影响CRC总生存率(OS)及无病生存率(RFS)的危险因素。结果:142例CRC并行放化疗的病人中有49例(34.5%)在治疗前被诊断为肌少症,多因素分析显示,术前肌少症与CRC病人的预后无显著相关性。治疗期间SMI丢失> 10%与较差的OS[HR=9.46;95%CI:3.49~25.63;P <0.001]和RFS(HR=11.79;95%CI:4.25~32.72;P <0.001)独立相关。治疗期间VATI增加>10%是影响OS(HR=3.06;95%CI:1.08~8.64;P=0.034)和RFS(HR=3.19;95%CI:1.07~9.53;P <0.038)的独立危险因素。结论:治疗前后SMI和VATI的变化可评估CRC病人的临床结局。在治疗期间准确掌握病人机体成分变化并加以干预,有利于改善CRC病人的预后。

Objective:To investigate the role of CT-derived body composition measurement in predicting the prognosis of colorectal cancer(CRC) patients with radiotherapy.Methods:A total of 142 patients with CRC was included in this study.Abdominal CT Images of the patients before and after treatments were obtained from our hospital database and were retrospectively analyzed.The skeletal muscle index(SMI),visceral adiposity index(VATI) and subcutaneous adiposity index(SATI) were assessed at the third lumbar vertebra(L3) on abdominal imaging.Sarcopenia was defined according to the cut-off values reported in the literatures,and the risk factors influencing overall survival(OS) and disease-free survival(RFS) in CRC were analyzed using Cox regression models.Results:Basing on CTderived body composition measurements,49(34.5%) of 142 CRC patientswere diagnosed with sarcopeniabefore treatments which was not significantly associated with the prognosis of CRC patients.Loss of SMI(>10%) during treatments was independently associated with poorer OS [HR= 9.46;95% confidence interval(CI) 3.49 to 25.63;P<0.001] and RFS(HR = 11.79;95% CI,4.25 to 32.72;P<0.001).An increase(>10%) of VATI during treatments was an independent risk factor for OS(HR = 3.06;95% CI,1.08 to 8.64;P = 0.034),whileit was not significantly associated with RFS.Conclusions:Changes in of SMI and VATI before and after treatments could be used as predictors for clinical outcomes of CRC patients with radiotherapy.CT-derived body composition measurement at the L3 vertebra level might have potential to guild the clinical managements and is likely helpful for improving the prognosis of CRC patients.