术前腹部脂肪含量对胃癌根治术后远处转移的预测价值

The value of preoperative abdominal fat content in predicting distant metastasis of gastric cancer afterradical surgery

目的:探讨术前腹部脂肪含量与胃癌根治术后远处转移的相关性。方法:回顾性分析2015-2022年在本院行胃癌根治术且在术后进行长期随访的136例患者的临床和术前腹部CT检查资料。其中,47例在随访过程中发生远处转移,89例术后随访5年及以上未发现转移。采用QCT PRO软件在CT平扫图像上对腹部脂肪含量进行定量分析,测量L_(3)椎体中部层面皮下脂肪含量(SFA)、腹腔内脂肪含量(VFA)、椎后肌群肌内脂肪浸润程度(MFI),并计算VFA/SFA。采用独立样本t检验比较远处转移组与无转移组之间年龄、身高、体表面积(BSA)、L_(3)层面VFA/SFA的差异;采用Mann-Whitney U检验比较2组之间体重、BMI及L_(3)层面VFA、SFA和MFI的差异;采用χ^(2)检验比较2组之间性别构成及抽烟史、高血压史和糖尿病史出现率的差异;并将VFA、SFA、MFI和VFA/SFA纳入单因素及多因素二元logistic回归分析,筛选出胃癌发生远处转移的独立危险因素,并采用ROC曲线分析各指标预测胃癌发生远处转移的诊断效能并确定最佳截断值。结果:远处转移组L_(3)层面的VFA和VFA/SFA均较无转移组大,差异均有统计学意义(P<0.05);两组之间MFI及SFA的差异均无统计学意义(P>0.05)。单因素logistic回归分析发现L_(3)层面VFA和VFA/SFA可能是影响胃癌根治术后远处转移的影响因素(P<0.05);多因素Logistic回归分析发现L_(3)层面VFA/SFA是影响胃癌根治术后远处转移的独立影响因素(P<0.05)。ROC曲线分析结果显示VFA/SFA的AUC为0.710(0.618~0.803),临界值为1.71,相应的预测敏感度和特异度分别为51.1%和85.4%。结论:基于CT平扫图像测量的L_(3)层面VFA/SFA是胃癌根治术后远处转移的独立影响因素。

Objective:To investigate the correlation between preoperative abdominal fat content and distant metastasis after radical gastrectomy for gastric cancer.Methods:The clinical and preoperative abdominal CT data of 136 patients who underwent radical gastrectomy and long-term follow-up in our hospital from^(2)015 to 2022 were retrospectively analyzed.Among them,47 patients developed distant metastasis during the follow-up,and 89 patients were follow-ups for more than 5 years without metastasis.QCT PRO software was used to quantitatively analyze the abdominal fat content on CT plain scan images.Subcutaneous fat content(SFA),visceral fat content(VFA)and intramuscular fat infiltration(MFI)of posterior vertebral muscles were measured at the middle level of L_(3) vertebral body,and VFA/SFA was calculated.Independent sample t-test was used to compare the differences of age,height,body surface area(BSA)and VFA/SFA at L_(3) level between the distant metastasis group and the non-metastasis group.Mann-Whitney U-test was used to compare the differences of body weight,BMI,VFA,SFA and MFI at L_(3) level between the two groups.The t-test was used to compare the differences in gender,smoking history,hypertension history,and diabetes history between the two groups.Univariate and multivariate binary Logistic regression analysis was used to analyze VFA,SFA,MFI and VFA/SFA at L_(3) level to select the independent risk factors that may affect the distant metastasis of gastric cancer,and the ROC curve was used to analyze the diagnostic efficacy of each index in predicting distant metastasis of gastric cancer and determine the best cut-off value.Results:The VFA and VFA/SFA values at L_(3) level in the distant metastasis group were higher than those in the non-metastasis group,and the differences were statistically significant(P<0.05).There was no significant difference in MFI and SFA between the two groups(P>0.05).Univariate logistic regression analysis showed that VFA and VFA/SFA at L_(3) level may be the influencing factors of distant metastasis after radical gastrectomy for gastric cancer(P<0.05).Multivariate Logistic regression analysis showed that VFA/SFA at L_(3) level was an independent influencing factor of distant metastasis after radical gastrectomy for gastric cancer(P<0.05).ROC curve analysis showed that the AUC of VFA/SFA was 0.710(0.618~0.803),the critical value was 1.71,and the corresponding predictive sensitivity and specificity were 51.1%and 85.4%,respectively.Conclusion:VFA/SFA at L_(3) level based on plain CT images is an independent influencing factor for distant metastasis after radical gastrectomy for gastric cancer.