Lymph node metastasis in rectal cancer: comparison of MDCT and MR imaging for diagnostic accuracy

• DOI: 10.1007/s00261-019-02240-8
• Publication Date: 2019-10-04T05:48:46Z
• Authors: Yiyan Liu; Ziqiang Wen; Xinyue Yang; Baolan Lu; Xiaojuan Xiao; Yan Chen; Shenping Yu
• Keywords: Adult; Aged, 80 and over; Male; Rectal Neoplasms; Iohexol; Contrast Media; Middle Aged; Magnetic Resonance Imaging; Sensitivity and Specificity; 3. Good health; 03 medical and health sciences; 0302 clinical medicine; Lymphatic Metastasis; Humans; Lymph Node Excision; Female; Tomography, X-Ray Computed; Aged

To compare the diagnostic accuracies of MDCT and high-resolution MRI (HR-MRI) for regional nodal metastases with different short-axis diameter ranges in rectal cancer patients.Rectal adenocarcinoma patients who underwent both MDCT and HR-MRI before surgery were included. The maximum short-axis diameters of the nodes were measured, and were classified as benign or malignant on imaging findings. All of the nodes were subdivided as follows: ≤ 5 mm (Group A), > 5 mm and ≤ 10 mm (Group B) , and > 10 mm (Group C). The postoperative pathological reports were used as the standard, and the sensitivity, specificity, accuracy, ROC curve, and AUC value were calculated for each subgroup.A total of 592 nodes were included in the node-to-node evaluation. In Group A, the specificity and accuracy of HR-MRI were significantly higher than those of MDCT (99.28% vs. 93.99%, P < 0.001; 95.78% vs. 89.56%, P = 0.010; respectively). In Group B, the specificity and accuracy of HR-MRI were also higher than those of MDCT (98.36% vs. 55.74%, P < 0.001; 80.45% vs. 66.17%, P < 0.001; respectively). For Groups A and B, the AUCs of MDCT were both 0.65, whereas those of HR-MRI were 0.76 and 0.82, respectively. In Group C, all nine malignant nodes were correctly diagnosed metastases on MDCT, whereas one was misjudged as benign on HR-MRI.The diagnostic value of HR-MRI is superior to that of MDCT, with higher specificity, accuracy, and AUC values for HR-MRI than for MDCT.