Retrospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jan 14, 2015; 21(2): 556-562
Published online Jan 14, 2015. doi: 10.3748/wjg.v21.i2.556
Computed tomography and magnetic resonance imaging evaluation of lymph node metastasis in early colorectal cancer
Joonsung Choi, Soon Nam Oh, Dong-Myung Yeo, Won Kyung Kang, Chan-Kwon Jung, Sang Woo Kim, Michael Yong Park
Joonsung Choi, Soon Nam Oh, Dong-Myung Yeo, Michael Yong Park, Department of Radiology, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul 137-701, South Korea
Won Kyung Kang, Department of Surgery, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul 137-701, South Korea
Chan-Kwon Jung, Department of Hospital Pathology, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul 137-701, South Korea
Sang Woo Kim, Department of Internal Medicine, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul 137-701, South Korea
Author contributions: Choi J and Oh SN performed the majority of study and edited the manuscript; Yeo DM, Jung CK and Park MY involved in data analysis; Kang WK and Kim SW involved in data acquisition.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Soon Nam Oh, MD, Department of Radiology, Seoul St. Mary’s Hospital, The Catholic University of Korea, 2222 Banpo-daero, Seocho-gu, Seoul 137-701, South Korea. hiohsn@gmail.com
Telephone: +82-2-22581426 Fax: +82-2-5996771
Received: May 19, 2014
Peer-review started: May 19, 2014
First decision: June 10, 2014
Revised: June 30, 2014
Accepted: July 25, 2014
Article in press: July 25, 2014
Published online: January 14, 2015
Abstract

AIM: To assess the role of computed tomography (CT) and magnetic resonance imaging (MRI) and establish imaging criteria of lymph node metastasis in early colorectal cancer.

METHODS: One hundred and sixty patients with early colorectal cancer were evaluated for tumor location, clinical history of polypectomy, depth of tumor invasion, and lymph node metastasis. Two radiologists assessed preoperative CT and/or MRI for the primary tumor site detectability, the presence or absence of regional lymph node, and the size of the largest lymph node. Demographic, imaging, and pathologic findings were compared between the two groups of patients based on pathologic lymph node metastasis and optimal size criterion was obtained.

RESULTS: The locations of tumor were ascending, transverse, descending, sigmoid colon, and rectum. One hundred and sixty early colorectal cancers were classified into 3 groups based on the pathological depth of tumor invasion; mucosa, submucosa, and depth unavailable. A total of 20 (12.5%) cancers with submucosal invasion showed lymph node metastasis. Lymph nodes were detected on CT or MRI in 53 patients. The detection rate and size of lymph nodes were significantly higher (P = 0.000, P = 0.044, respectively) in patients with pathologic nodal metastasis than in patients without nodal metastasis. Receiver operating curve analysis showed that a cut-off value of 4.1 mm is optimal with a sensitivity of 78.6% and specificity of 75%.

CONCLUSION: The short diameter size criterion of ≥ 4.1 mm for metastatic lymph nodes was optimal for nodal staging in early colorectal cancer.

Keywords: Early colon cancer, Lymph node metastasis, Computed tomography, Magnetic resonance imaging, Lymph node size

Core tip: This study is the first study on the imaging criterion of lymph node metastasis in early colorectal cancer. The results suggest that the detection rate and the size of lymph nodes (LNs) were significantly higher in patients with pathologic nodal metastasis. The optimal size criterion for LN metastasis was ≥ 4.1 mm in early colorectal cancer.