MRI在直肠癌术前分期中的准确性分析

Analysis of accuracy of preoperative MRI staging

目的分析MRI在直肠癌术前分期中的准确性。方法选择2012年12月~2014年4月于中山大学附属第六医院接受MRI检查并通过活检组织病理确诊的原发性直肠癌患者154例,通过对比其术后病理分期,分析MRI术前分期准确率。结果将T分期分为T_(3~4)期及T_(0~2)期,其准确率、灵敏度、特异度、阳性预测值和阴性预测值分别为77.9%、93.3%、46%、78.2%和76.7%。而N分期分为N^+期和N_0期,分别是57.1%、78.2%、45.5%、44.3%和78.9%。TNM分期分为Ⅱ~Ⅲ期和0~Ⅰ期,分别是79.9%、93.1%、39.5%、82.4%和65.2%。结论MRI是一种准确的直肠癌术前分期方法,TN分期均具有较高的灵敏度,但是特异度不高,可能会导致过度分期。

Objective To evaluate the accuracy of preoperative MRI staging in primary rectal cancer patients. Methods From December 2012 to April 2014, in Sixth Affiliated Hospital of Sun Yat-Sen University, 154 primary rectal cancer patients underwent MRI before surgery were selected. The accuracy of preoperative MRI was analyzed by comparing with postoperative pathological stage. Results T stage was divided into T3-4 stage and TOE stage, the accuracy, sensitivity, specificity, PPV, NPV were 77.9%, 93.3%, 46%, 78.2%, 76.7%. N stage was divided into N^＋ stage and No stage, the accuracy, sensitivity, specificity, PPV, NPV were 57.1%, 78.2%, 45.5%, 44.3%, 78.9%. TNM stage was divided into II- III stage and 0- I stage, he accuracy, sensitivity, specificity, PPV, NPV were 79.9%, 93.1%, 39.5%, 82.4%, 65.2%. Conclusion MRI can be applied as a useful tool in rectal cancer staging. Both T category and nodal metastasis has high sensitivity. But its low specificity may lead to over-staging.