title: Computed tomography and magnetic resonance imaging evaluation of lymph node metastasis in early colorectal cancer.
abstract: OBJECTIVE
  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%.
  
  
  CONCLUSIONS
  The short diameter size criterion of ≥ 4.1 mm for metastatic lymph nodes was optimal for nodal staging in early colorectal cancer.
authors.affiliation: 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.
authors.forename: Joonsung
authors.initials: J
authors.lastname: Choi
authors.affiliation: 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.
authors.forename: Soon Nam
authors.initials: SN
authors.lastname: Oh
authors.affiliation: 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.
authors.forename: Dong-Myung
authors.initials: DM
authors.lastname: Yeo
authors.affiliation: 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.
authors.forename: Won Kyung
authors.initials: WK
authors.lastname: Kang
authors.affiliation: 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.
authors.forename: Chan-Kwon
authors.initials: CK
authors.lastname: Jung
authors.affiliation: 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.
authors.forename: Sang Woo
authors.initials: SW
authors.lastname: Kim
authors.affiliation: 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.
authors.forename: Michael Yong
authors.initials: MY
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D055088:Early Detection of Cancer / Q000379:methods*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D009361:Neoplasm Invasiveness; D011237:Predictive Value of Tests; D055815:Young Adult
keywords: Computed tomography; Early colon cancer; Lymph node metastasis; Lymph node size; Magnetic resonance imaging