title: Prediction of Lateral Pelvic Lymph-Node Metastasis in Low Rectal Cancer by Magnetic Resonance Imaging.
abstract: OBJECTIVE
  This study was designed to evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) for lateral pelvic lymph-node metastasis.
  
  
  METHODS
  Eighty-four patients with primary lower rectal cancer were examined by MRI and subsequently underwent radical surgery with lateral pelvic lymph-node dissection, without preoperative treatment. Lateral lymph-node metastases were assessed preoperatively by MRI, and the results were compared with the histopathological findings. The criterion for lateral lymph-node metastasis was any recognizable lymph node in the pelvic wall, regardless of diameter.
  
  
  RESULTS
  Lateral pelvic lymph-node metastasis was diagnosed on preoperative MRI in 16 patients (19.9 %). The overall patient-based sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of MRI were 75, 69.1, 36.4, 92.2, and 70.2 %, respectively. When a cut-off value of 10 mm was used for diagnosis, the corresponding values were 43.8, 98.5, 87.5, 88.1, and 88.1 %, respectively. The mean diameter of metastatic nodes (14.7 mm) was significantly larger than that of negative nodes (5.7 mm; P < 0.01).
  
  
  CONCLUSIONS
  MRI is an effective technique for predicting lateral pelvic node involvement and thus may facilitate preoperative decision-making in rectal cancer treatment. A cut-off value of 10 mm is useful for avoiding unnecessary lateral lymph-node dissection.
authors.affiliation: Department of Gastroenterological Surgery, Yokohama City University Graduate School Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan. a.ishibe1225@gmail.com.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ishibe
authors.affiliation: Department of Surgery, Gastroenterological Center, Graduate School of Medicine, Yokohama City University, Yokohama, Japan.
authors.forename: Mitsuyoshi
authors.initials: M
authors.lastname: Ota
authors.affiliation: Department of Gastroenterological Surgery, Yokohama City University Graduate School Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Watanabe
authors.affiliation: Department of Gastroenterological Surgery, Yokohama City University Graduate School Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Suwa
authors.affiliation: Department of Gastroenterological Surgery, Yokohama City University Graduate School Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Suzuki
authors.affiliation: Department of Surgery, Gastroenterological Center, Graduate School of Medicine, Yokohama City University, Yokohama, Japan.
authors.forename: Amane
authors.initials: A
authors.lastname: Kanazawa
authors.affiliation: Department of Gastroenterological Surgery, Yokohama City University Graduate School Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan.
authors.forename: Kazuteru
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: Department of Gastroenterological Surgery, Yokohama City University Graduate School Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ichikawa
authors.affiliation: Department of Surgery, Gastroenterological Center, Graduate School of Medicine, Yokohama City University, Yokohama, Japan.
authors.forename: Chikara
authors.initials: C
authors.lastname: Kunisaki
authors.affiliation: Department of Gastroenterological Surgery, Yokohama City University Graduate School Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan.
authors.forename: Itaru
authors.initials: I
authors.lastname: Endo
mesh_terms: D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010388:Pelvis; D011379:Prognosis; D012372:ROC Curve; D012004:Rectal Neoplasms / Q000175:diagnosis / Q000556:secondary*