1Colorectal Cancer Center, Kyungpook National University Medical Center, School of Medicine, Kyungpook National University, Daegu, Korea 2Department of Radiology, Kyungpook National University Hospital, School of Medicine, Kyungpook National University, Daegu, Korea 3Department of Anesthesiology and Pain Medicine, College of Medicine, Chung-Ang University, Seoul, Republic of Korea.
Dis Colon Rectum. 2014 Jan;57(1):32-8. doi: 10.1097/DCR.0000000000000004.
Few studies that meticulously match individual lymph nodes seen on MRI with their precise histologic counterparts after total mesorectal excision have been reported.
The objective of this study was to determine whether preoperative MRI could detect lymph node metastases accurately in the node-by-node analysis.
This was a prospective, observational cohort study.
The study was conducted at a tertiary-care hospital.
Forty patients with rectal cancer were enrolled.
Specimens were assessed using MRI for clinical staging. After surgical resection of the tumor, the specimens were again imaged with ex vivo ultrasound scan to localize the perirectal node. The locations of each lymph node were precisely matched with its corresponding magnetic resonance image to enable a node-for-node comparison of magnetic resonance images and histologic findings.
Agreement between MRI and histologic assessment of T stage was 82.5%. Of the 341 nodes harvested, 120 were too small (<3 mm) to be depicted on magnetic resonance images, and 18 of these contained metastasis (15%). A correlation between the results of MRI and histopathology was feasible for 205 lymph nodes, and the overall success rate of matching between the 2 techniques was 91.1% (205 of 221). Preoperative MRI revealed a node-by-node sensitivity and positive predictive value of 58.0%, and 61.7%. There was no difference in the diagnostic accuracy between the primary surgery subgroup and preoperative radiation subgroups.
The study is limited by its heterogeneity of cohorts including the subgroup with preoperative chemoradiation and the lack of preoperative ultrasound assessment.
Preoperative MRI was moderately accurate for the prediction of mesorectal lymph node metastasis. Moreover, preoperative MRI was insufficient for detecting small lymph nodes (<3 mm) with metastasis.
鲜有研究能细致地将 MRI 上所见的个体淋巴结与全直肠系膜切除术后的精确组织学对应物相匹配。
本研究旨在确定术前 MRI 是否能在逐个淋巴结分析中准确检测淋巴结转移。
这是一项前瞻性、观察性队列研究。
研究在一家三级保健医院进行。
纳入 40 例直肠癌患者。
采用 MRI 对标本进行临床分期评估。在肿瘤切除术后，再次对标本进行离体超声扫描以定位直肠周围淋巴结。每个淋巴结的位置都与相应的磁共振图像精确匹配，以实现磁共振图像与组织学发现的逐个淋巴结比较。
MRI 与 T 分期的组织学评估之间的一致性为 82.5%。在采集的 341 个淋巴结中，有 120 个太小（<3 mm）而无法在磁共振图像上显示，其中 18 个含有转移（15%）。MRI 结果与组织病理学之间的相关性对于 205 个淋巴结是可行的，两种技术之间的总体匹配成功率为 91.1%（205 个中有 205 个）。术前 MRI 显示逐个淋巴结的敏感性和阳性预测值分别为 58.0%和 61.7%。在原发性手术亚组和术前放疗亚组之间，诊断准确性没有差异。
该研究受到其队列异质性的限制，包括术前放化疗亚组和缺乏术前超声评估。
术前 MRI 对预测直肠系膜淋巴结转移的准确性中等。此外，术前 MRI 不足以检测到有转移的小淋巴结（<3 mm）。
