title: Prospective assessment of MRI for imaging retroperitoneal metastases from testicular germ cell tumours.
abstract: OBJECTIVE
  To determine the sensitivity of magnetic resonance imaging (MRI) in the detection of retroperitoneal lymph nodes in patients with testicular germ cell tumours (TGCT).
  
  
  METHODS
  A prospective study of 52 patients (mean age 34 years, range 18-54 years) was performed. Imaging of the retroperitoneum was performed using multidetector computed tomography (CT) and 1.5 T MRI systems. The CT and MRI images were read independently by three observers. The number, size, and site of enlarged nodes (> or =10 mm maximum short axis diameter) were recorded. Retroperitoneal nodal detection on MRI was compared to CT.
  
  
  RESULTS
  Twenty-two (42%) of the 52 patients had no retroperitoneal disease; in remaining 30 patients 51 enlarged nodes were identified. On a per patient basis readers 1, 2, and 3 identified nodal disease in 28 of 29, 29 of 30, and 24 of 30 patients, respectively, using MRI compared to CT. Thus for experienced radiologists (readers 1 and 2) MRI is comparable to CT for nodal detection (i.e., this study excludes MRI being inferior to CT with 80% power and 5% type 1 error).
  
  
  CONCLUSIONS
  MRI offers an alternative method for staging the retroperitoneum in young patients being followed for TGCT and has the major advantage of avoiding exposure to ionizing radiation.
authors.affiliation: Department of Radiology, Institute of Cancer Research & Royal Marsden Hospital, Sutton, Surrey, UK. aslam.sohaib@rmh.nhs.uk
authors.forename: S A
authors.initials: SA
authors.lastname: Sohaib
authors.forename: D M
authors.initials: DM
authors.lastname: Koh
authors.forename: Y
authors.initials: Y
authors.lastname: Barbachano
authors.forename: J
authors.initials: J
authors.lastname: Parikh
authors.forename: J E S
authors.initials: JE
authors.lastname: Husband
authors.forename: D P
authors.initials: DP
authors.lastname: Dearnaley
authors.forename: A
authors.initials: A
authors.lastname: Horwich
authors.forename: R
authors.initials: R
authors.lastname: Huddart
mesh_terms: D000293:Adolescent; D000328:Adult; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods / Q000592:standards*; D008297:Male; D008875:Middle Aged; D009373:Neoplasms, Germ Cell and Embryonal / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000556:secondary*; D011446:Prospective Studies; D015203:Reproducibility of Results; D012186:Retroperitoneal Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000556:secondary*; D012680:Sensitivity and Specificity; D013736:Testicular Neoplasms; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000592:standards*; D055815:Young Adult