1Department of General Surgery, Colorectal Unit, Hospital La Fe, University of Valencia, Valencia, Spain 2Department of General Surgery, Colorectal Unit, Hospital Clinico Universitario, University of Valencia, Valencia, Spain 3Imaging Department, ERESA Grupo Médico, Valencia, Spain.
Dis Colon Rectum. 2014 Jun;57(6):709-14. doi: 10.1097/DCR.0000000000000096.
Accuracy of MRI in assessing mesorectal fascia and predicting circumferential resection margin decreases in low anterior rectal tumors.
The purpose of this work was to evaluate the accuracy of endorectal ultrasound in predicting the pathologic circumferential resection margin in low rectal anterior tumors and to compare it with MRI findings.
This was a prospective series comparing the preoperative circumferential resection margin assessed by endorectal ultrasound and MRI with pathologic examination.
The study was conducted by a specialized colorectal multidisciplinary team at a tertiary teaching hospital.
Between 2002 and 2008, 76 patients with mid to low rectal cancer were preoperatively evaluated by endorectal ultrasound and MRI and underwent total mesorectal excision without neoadjuvant radiochemotherapy. Twenty-seven patients with posterior or postero-lateral tumors were excluded, leaving 49 patients with anterior or antero-lateral tumors for the present subanalysis. We compared preoperative circumferential resection margin status using endorectal ultrasound and MRI with pathologic examination.
We conducted a comparison between preoperative circumferential resection margin status and pathologic examination after total mesorectal excision surgery.
Accuracy in predicting pathologic circumferential resection margin status was measured.
Overall accuracy of endorectal ultrasound and MRI in assessing circumferential resection margin status was 83.7% and 91.8%, with negative predictive values of 97.2% and 97.5%. When focusing on low rectal tumors, the overall accuracy of endorectal ultrasound increased to 87.5%, whereas the accuracy of MRI decreased to 87.5%, with a negative predictive value of 95.6% for both diagnostic tests.
The sample size is small, and interobserver variability in radiologic assessment was not evaluated.
Endorectal ultrasound can help MRI in predicting circumferential resection margin involvement in mid to low anterior rectal cancer, especially at the low third of the rectum, with a high negative predictive value.
MRI 评估中低位直肠系膜筋膜和预测环周切缘的准确性降低。
本研究旨在评估腔内超声预测低位直肠前肿瘤病理环周切缘的准确性，并与 MRI 结果进行比较。
这是一项比较腔内超声和 MRI 术前评估与病理检查的前瞻性系列研究。
本研究由一家三级教学医院的专门结直肠多学科团队进行。
2002 年至 2008 年间，76 例中低位直肠癌患者接受了腔内超声和 MRI 术前评估，并接受了无新辅助放化疗的全直肠系膜切除术。排除了 27 例后壁或后外侧肿瘤患者，留下 49 例前壁或前外侧肿瘤进行本次亚分析。我们比较了术前环周切缘状态，使用腔内超声和 MRI 与病理检查。
我们比较了全直肠系膜切除术后术前环周切缘状态和病理检查。
预测病理环周切缘状态的准确性。
腔内超声和 MRI 评估环周切缘状态的总体准确率分别为 83.7%和 91.8%，阴性预测值分别为 97.2%和 97.5%。当聚焦于低位直肠肿瘤时，腔内超声的总体准确率增加到 87.5%，而 MRI 的准确率下降到 87.5%，两种诊断试验的阴性预测值均为 95.6%。
样本量小，且未评估放射学评估的观察者间变异性。
腔内超声有助于 MRI 预测中低位直肠前癌的环周切缘受累，尤其是在直肠下段，具有较高的阴性预测值。
