高分辨率DWI-RESOLVE序列对直肠癌术前分期的应用价值

The Value of High Resolution DWI-RESOLVE Sequence in the Staging of Preoperative Rectal Cancer

目的:本研究旨在探讨高分辨率DWI-RESOLVE序列对直肠癌术前T分期的价值。方法:回顾性分析在我院经术后病理证实的直肠腺癌患者40例(T1-T2为A组,T3-T4为B组)。全部研究对象均完成RESOLVE序列扫描,b值=0、1000s/mm^2。两名医师独立分析图像,得到感兴趣区的ADC值。计算组内相关系数(ICC)分析两名医师测量结果的一致性。根据病理结果制作受试者操作特性曲线(ROC),计算曲线下面积(AUC),分析得出最佳诊断阈值及敏感度和特异度。结果:40例直肠癌术后病理T分期:T1-T2 17例,T3-T4 23例。A组的平均ADC值为(1.230±0.160)×10^(-3)mm^2/s(医师1)和(1.200±0.166)×10^(-3)mm^2/s(医师2),高于B组的平均ADC值(0.973±0.216)×10^(-3)mm^2/s(医师1)和(0.948±0.181)×10^(-3)mm^2/s(医师2)。两名医师测量参数的ICC系数是0.947。ROC曲线下面积是0.850,敏感度76.47%,特异度78.26%,诊断阈值为1.13×10^(-3)mm^2/s。结论:RESOLVE序列对于术前判断直肠癌病灶是否突破固有肌层具有较高的参考价值。

Purpose： To explore the performance of high resolution DWI - RESOLVE sequence in the T staging of preoperative primary rectal cancer. Methods： Forty patients with preoperative primary rectal cancer were undergone with DWI - RESOLVE （b=0, 1000s/mm^2） in our hospital by using Siemens 3T Skyra scanner. All patients were confirmed by pathology results, and divided into two groups： group A （T1-T2） and group B （T3-T4）. Two experienced radiologists drew regions of interest （ROI） on the apparent diffusion coefficient （ADC） map to calculate mean ADC value of each tumor by a prototype post-processing software, and inter-observer agreement between the two radiologists was calculated. Receiver operating characteristic （ROC） analysis was used to analyze and compare the parameters between the two groups. Results： Pathological examinations revealed 17 T1-T2 and 23 T3-T4 rectal adenocarcinomas. The mean ADC value of group A was （1.230±0.160）x 10-3mm^2/s （physician 1） and （1.200±0.166）- 10-3mm^2/s （physician 2）, which was higher than that in group B （0.973±0.216）×10-3mm^2/s （physician 1） and （0.948±0.181）×10-3mm^2/s （physician 2） （P〈0.05）. The intra-class correlation coefficient （ICC） was 0.947. The area under curve （AUC） was 0.850, sensitivity 76.47%, specificity 78.26%, the ADC value threshold was set as 1.13±10^-3mm^2/s. Conelusion： RESOLVE can be used to improve the efficiency in assessment of whether the muscularis propria layer was involved by the lesion for the preoperative evaluation of rectal cancer.