title: Lymph node metastases from gastric cancer: gadofluorine M and gadopentetate dimeglumine MR imaging in a rabbit model.
abstract: OBJECTIVE
  To compare the diagnostic performance of gadofluorine M with that of gadopentetate dimeglumine in the diagnosis of lymph node metastases with magnetic resonance (MR) imaging in a rabbit model of gastric cancer.
  
  
  METHODS
  The study protocol was approved by the institutional animal care committee. VX2 carcinomas were inoculated into the wall of the stomach in 20 rabbits. Gadopentetate dimeglumine-enhanced MR imaging was performed 4-6 weeks after inoculation, and gadofluorine M-enhanced MR imaging was performed approximately 24 hours later. Both MR imaging sets were analyzed separately and independently by four radiologists with respect to confidence level regarding the presence of metastases in lymph nodes and lymph node conspicuity. Statistical analysis was performed by using multiple-reader multiple-case (MRMC) receiver operating characteristic curve analysis and the Wilcoxon signed rank test.
  
  
  RESULTS
  Metastases were confirmed at pathologic analysis in 32 of 104 lymph nodes from 16 rabbits. The area under the receiver operating characteristic curve (AUC) for confidence regarding the presence of metastases in lymph nodes was significantly greater for gadofluorine M than for gadopentetate dimeglumine (AUC, 0.947 vs 0.894; P = .009). However, most (81%, 25 of 32) metastatic nodes were necrotic, and no significant difference was obtained in nonnecrotic nodes. For lymph node conspicuity, the gadofluorine M MR imaging set was assigned a significantly higher score than was the gadopentetate dimeglumine MR imaging set by all readers (P < .001).
  
  
  CONCLUSIONS
  Gadofluorine M showed significantly higher accuracy and better conspicuity than gadopentetate dimeglumine in the diagnosis of metastatic nodes, most of which were necrotic, in this animal model of gastric cancer.
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Byung Ihn
authors.initials: BI
authors.lastname: Choi
authors.forename: Kyu Ri
authors.initials: KR
authors.lastname: Son
authors.forename: Jeong Min
authors.initials: JM
authors.lastname: Lee
authors.forename: Soo Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: Hee Sun
authors.initials: HS
authors.lastname: Park
authors.forename: Jung Min
authors.initials: JM
authors.lastname: Chang
authors.forename: Seung Hong
authors.initials: SH
authors.lastname: Choi
authors.forename: Min A
authors.initials: MA
authors.lastname: Kim
authors.forename: Woo Kyung
authors.initials: WK
authors.lastname: Moon
mesh_terms: D000818:Animals; D003287:Contrast Media; D004195:Disease Models, Animal; D005466:Fluorocarbons; D019786:Gadolinium DTPA; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009367:Neoplasm Staging; D009942:Organometallic Compounds; D010865:Pilot Projects; D012372:ROC Curve; D011817:Rabbits; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D013274:Stomach Neoplasms / Q000473:pathology*
chemical_list: D003287:Contrast Media; D005466:Fluorocarbons; D009942:Organometallic Compounds; C517961:gadofluorine M; D019786:Gadolinium DTPA