title: MRI for preoperative staging of renal cell carcinoma using the 1997 TNM classification: comparison with surgical and pathologic staging.
abstract: OBJECTIVE
  The purpose of our study was to determine the accuracy of MRI for preoperative staging of renal cell carcinoma using the 1997 TNM classification.
  
  
  METHODS
  We conducted a retrospective review of MRI performed in 40 consecutive patients with 42 renal cell carcinomas before radical (n = 35) or partial (n = 4) nephrectomy or exploratory laparotomy (n = 3). The interval between imaging and surgery ranged from 1 to 59 days (mean, 17.9 days). Imaging was performed with T1- and T2-weighted, dynamic gadolinium-enhanced, and time-of-flight sequences. MRI and surgical-pathologic staging was performed using the 1997 TNM staging system. MRI staging was compared with surgical-pathologic staging as the gold standard. Agreement between the two staging methods was assessed using the kappa statistic.
  
  
  RESULTS
  Agreement between MRI and surgical-pathologic staging was good for T staging (kappa = 0.72 and 0.78 for reviewers 1 and 2 respectively), poor for N staging (kappa = 0.13, both reviewers), good for M staging (kappa = 0.66, both reviewers), and excellent for the assessment of venous involvement (kappa = 0.93, both reviewers). MRI overestimated the T stage in five patients and the N stage in five and underestimated the T stage in three, the N stage in four, the M stage in one, and the extent of venous thrombosis in two patients.
  
  
  CONCLUSIONS
  MRI is a reliable method for preoperative staging of renal cell carcinoma using the 1997 TNM classification, in particular for assessing venous involvement.
authors.affiliation: Department of Radiology/MRI UH-B2B311, University of Michigan Health System, 1500 E Medical Center Dr., Ann Arbor, MI 48109-0003, USA.
authors.forename: F Bilge
authors.initials: FB
authors.lastname: Ergen
authors.forename: Hero K
authors.initials: HK
authors.lastname: Hussain
authors.forename: Elaine M
authors.initials: EM
authors.lastname: Caoili
authors.forename: Melvyn
authors.initials: M
authors.lastname: Korobkin
authors.forename: Ruth C
authors.initials: RC
authors.lastname: Carlos
authors.forename: William J
authors.initials: WJ
authors.lastname: Weadock
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Johnson
authors.forename: Rajal
authors.initials: R
authors.lastname: Shah
authors.forename: Satoru
authors.initials: S
authors.lastname: Hayasaka
authors.forename: Isaac R
authors.initials: IR
authors.lastname: Francis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000145:classification / Q000473:pathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000145:classification / Q000473:pathology* / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011300:Preoperative Care; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013997:Time Factors