基于MRI多参数联合对T3期直肠癌亚分期的诊断价值  

Diagnostic value of multi-parameter MRI for substages of the stage T3 rectal cancer

作　　者：许蕾[1] 邵瑞 李红蕾 王椋[1] XU Lei;SHAO Rui;LI Hong-lei(Medical Imaging Consultation Center,Shenli Oilfield Central Hospital,Shandong 257034,China)

机构地区：[1]胜利油田中心医院医学影像会诊中心,山东257034

出　　处：《放射学实践》2020年第4期514-518,共5页Radiologic Practice

摘　　要：目的:探讨多参数MRI对T3期直肠癌亚分期的诊断价值。方法:回顾性分析经手术病理证实T3期直肠癌患者52例且术前均行MRI直肠高分辨扫描、动态增强扫描(DCE)及扩散加权成像(DWI)检查。根据明确病理评价结果将52例患者按肿瘤浸润直肠系膜最大深度分为T3Ⅰ、T3Ⅱ两组,采用χ^2检验比较2组病变整体形态学指标、壁外索条形态学指标、时间-信号强度曲线(TIC)类型、DWI扩散受限分布位置指标的差异。采用独立样本t检验比较2组病变DCE半定量参数值[包括达峰时间(Tmax)和早期强化率(EER)]的差异。以病理结果为应变量,自变量采用上述具有统计学差异的指标,建立Logisitc回归模型构建联合参数并评价其诊断效能。结果:肿瘤周径及壁外索条影形状、DWI上扩散受限区域的分布位置在两组间的差异具有统计学意义(χ^2=6.994,7.917和7.834;P值均<0.01)。两组病变在DCE-MRI上的半定量参数EER值的差异具有统计学意义(t=7.585,P<0.01)。采用Logisitc回归模型构建回归方程,病变周径+壁外索条+DWI扩散受限分布位置+EER值联合诊断的约登指数最高为0.73,ROC曲线下面积(Az)为0.887(95%CI:0.847~0.912),诊断敏感度及特异度分别为85.24%和87.34%。结论:多参数信息联合壁外索条形态学指标、周径、EER、DWI扩散受限分布位置对T3期直肠癌亚分期具有较高的诊断效能。Objective:To investigate the diagnostic value of multi-parameter MRI in diagnosis of substages of the stage T3 rectal cancer.Methods:52 patients with stage T3 rectal cancer confirmed by surgical pathology were retrospectively analyzed.All underwent DCE-MRI and diffusion-weighted imaging(DWI)examinations.According to the pathological results,the 52 patients were divided into T3Ⅰgroup and T3Ⅱgroup.χ^2-test was used to compare overall morphology indexes,morphologic signs of adjacent invasion and TIC curve types on DCE-MRI and distribution location of limited diffusion on DWI between the 2 groups.Independent sample t-test was used to compare the differences in semi-quantitative parameters including the time of maximum enhancement(Tmax)and early enhancement ratio(EER)on DCE-MRI between the two groups.The pathological results were used as the depen-dent variables,indexes with statistical differences were used as the independent variables to construct a logistic regression equation,and the diagnostic efficacy of the stepwise combined parameters was eva-luate by ROC curve analysis.Results:There were significant differences in the cross-section diameters of tumor and morphologic signs of adjacent invasion between the T3Ⅰgroup and T3Ⅱgroup(χ^2=6.994,P<0.01;χ^2=7.917,P<0.01).Significant differences were found in the number of cases with different distribution locations of limited diffusion on DWI(χ^2=7.834,P<0.01)and the semi-quantitative parameters early enhancement ratio(EER)between the 2 groups(t=7.585,P<0.01).The maximum Youden index of a newly-constructed parameter combination:morphological indexes of cross-section diameters,signs of adjacent invasion,distribution locations of limited diffusion on DWI,and EER was 0.73 for a combined diagnosis,the area under ROC curve(Az)was 0.887(95%CI:0.847~0.912),and the diagnostic sensitivity and specificity were 85.24%and 87.34%,respectively.Conclusion:Multi-parameter MRI can provide higher diagnostic efficacy for substages of the stage T3 rectal cancer.

关 键 词：直肠肿瘤 肿瘤分期 磁共振成像 Logisitc回归分析 诊断效能 

分 类 号：R445.2[医药卫生—影像医学与核医学] R735.3[医药卫生—诊断学]