小视野T2WI直肠癌T分期临床应用研究

Clinical application of small field-of-view T2WI in rectal carcinoma T staging

目的探讨小视野T2WI对直肠癌T分期的应用价值以及肿瘤体积与其T分期之间的相关性。材料与方法搜集经肠镜证实为直肠癌的患者90例,于术前行磁共振常规序列和小视野、薄层T2WI序列扫描,由2名医师同时对其进行T分期,并逐层勾画肿瘤边界,获得每层肿瘤面积,计算并记录肿瘤体积。比较磁共振小视野T2WI对直肠癌T分期与病理T分期的一致性,分析小视野T2WI测得的肿瘤体积与病理T分期的相关性。结果应用小视野T2WI诊断直肠癌T分期与病理T分期具有较好的一致性(Kappa=0.771),诊断准确率为84.44%,其中T1期肿瘤诊断的准确度、敏感度和特异度分别为96.67%、80.00%、97.65%;T2期分别为88.89%、80.00%、92.31%;T3期分别为86.67%、82.05%、90.20%;T4a期分别为96.67%、95.24%、97.10%。磁共振上测量的肿瘤体积与病理T分期呈中度相关(r=0.657,P<0.05)。结论小视野T2WI在直肠癌T分期方面具有较高的应用价值,对术前肿瘤T分期的评估及治疗方案的制订具有一定的潜在应用价值。

Objective To investigate the value of small field-of-view T2 weighted imaging in rectal carcinoma T staging and the correlation between tumor volume and T staging. Materials and methods： Ninety cases with rectal carcinoma confrmed by colonoscopy underwent MRI scanning, including conventional T2 weighted imaging and small feld-of-view, thin-section T2 weighted imaging. Two radiologists analyzed T staging at the same time, and drew the outline of tumor boundary, in order to acquire tumor size of each layer and to calculate tumor volume. Consistency between T staging by small feld-of-view T2WI and pathological method was compared, and the correlation between tumor volume by small feld-of-view T2WI and pathological T staging was analyzed. Results： Small feld of view T2 weighted imaging for T stage was highly consistent with pathological stage （Kappa=0.771）. The diagnostic accuracy in predicting T stage was 84.44%. The accuracy, sensitivity and specifcity for tumor of T1 stage were 96.67%, 80.00%, 97.65%, respectively. The accuracy, sensitivity and specificity for tumor of T2 stage were 88.89%, 80.00%, 92.31%, respectively. The accuracy, sensitivity and specifcity for tumor of T3 stage were 86.67%, 82.05%, 90.20%, respectively. the accuracy, sensitivity and specifcity for tumor of T4a stage were 96.67%, 95.24%, 97.10%, respectively. Moderate correlation in tumor volume was detected between MRI measurement and pathological T staging （r=0.657, P〈0.05）. Conclusions： Small feld-of-view T2WI has relatively high application value in rectal carcinoma T staging, as well as in the tumor T staging evaluation before surgery and the selection of therapeutic schedule.