title: The accuracy of magnetic resonance imaging in staging of vulvar cancer: a retrospective multi-centre study.
abstract: OBJECTIVE
  To retrospectively evaluate the diagnostic accuracy and clinical relevance of magnetic resonance imaging (MRI) in the management of primary and recurrent vulvar cancer and to examine the added value of contrast-enhanced MRI (CE-MRI).
  
  
  METHODS
  The research ethics committee waived informed consent for this study of 49 patients with vulvar cancer (36 primary and 13 recurrent) who underwent MRI before surgery at three major cancer centers from December 2003 to January 2008. CE-MRI was available for 31 patients (20 primary and 11 recurrent). MR images were retrospectively evaluated by three radiologists for tumor size and stage. Lymph nodes with a short axis >5 mm were measured and scored for contour, presence of necrosis, loss of fatty hilum, signal intensity relative to the vulvar lesion, and reader's diagnosis of lymph node metastasis. Scoring was repeated for CE-MRI. Histopathology constituted the reference standard.
  
  
  RESULTS
  The size of the vulvar lesion was accurately characterized on MRI in 83% of patients. Accuracy in staging of primary vulvar cancers on unenhanced MRI was 69.4% (n=36). Adding CE-MRI increased lesion detection and raised staging accuracy from 75% to 85% (n=20). For groin lymph node metastasis prediction, the ratio of the short- to the long-axis diameter and the reader's diagnosis of lymph node metastasis yielded accuracy of 85% and 87%, respectively, in groin-by-groin analysis.
  
  
  CONCLUSIONS
  MRI can be useful in accurately assessing the size of vulvar lesion and groin lymph node metastasis. CE-MRI may be of help in improving local staging.
authors.affiliation: Department of Radiology, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK. mk435@cam.ac.uk
authors.forename: Masako Yano
authors.initials: MY
authors.lastname: Kataoka
authors.forename: Evis
authors.initials: E
authors.lastname: Sala
authors.forename: Peter
authors.initials: P
authors.lastname: Baldwin
authors.forename: Caroline
authors.initials: C
authors.lastname: Reinhold
authors.forename: Alex
authors.initials: A
authors.lastname: Farhadi
authors.forename: Turtko
authors.initials: T
authors.lastname: Hudolin
authors.forename: Hedvig
authors.initials: H
authors.lastname: Hricak
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D012189:Retrospective Studies; D014846:Vulvar Neoplasms / Q000175:diagnosis* / Q000473:pathology* / Q000601:surgery