title: Diagnostic accuracy of preoperative computed tomography used alone to detect lymph-node involvement at radical nephrectomy.
abstract: OBJECTIVE
  The aim of this study was to compare preoperative computed tomography (CT) with pathological findings in patients undergoing lymphadenectomy at the time of nephrectomy for renal cancer-associated lymphadenopathy.
  
  
  METHODS
  Data from 515 consecutive nephrectomy surgeries (2004-2012) in a single university-affiliated centre were analysed to identify patients who had undergone lymph-node dissection concomitant with nephrectomy. Preoperative CT imaging was subjected to multiple repeated independent blinded reviews (two radiologists and one surgeon, each individually and on two separate occasions). Retroperitoneal lymph-node status was subjectively categorized (in a manner not based purely on size criteria) at each review as: 1 = unequivocally positive, 2 = equivocally positive, 3 = equivocally negative, or 4 = unequivocally negative. These findings were compared with pathological analysis, and interobserver and intraobserver agreement was assessed using non-weighted kappa () statistics.
  
  
  RESULTS
  In total, 71 patients were stratified as category 1 (n = 18), 2 (n = 14), 3 (n = 31) and 4 (n = 8); pathological lymph-node metastasis was present in 14 (78%), four (28%), four (13%) and zero patients, respectively. Sensitivity, specificity, positive and negative predictive values for preoperative CT were 82%, 71%, 56% and 90%, respectively. Intraobserver agreement was greater for the radiologists (values 0.490, 0.540) than for the surgeon (value 0.393). Interobserver agreement was strongest for radiological category 1 (unequivocally positive; value 0.75). Receiver operating characteristics curves did not reveal significant differences in any observer accuracy.
  
  
  CONCLUSIONS
  Contrary to concerns about a high false-positive rate, metastasis within regional lymph nodes can be predicted with reasonable accuracy by preoperative CT imaging alone.
authors.affiliation: Departments of Urology and.
authors.forename: Stephen S
authors.initials: SS
authors.lastname: Connolly
authors.forename: Aditya
authors.initials: A
authors.lastname: Raja
authors.forename: Helen
authors.initials: H
authors.lastname: Stunell
authors.forename: Deepak
authors.initials: D
authors.lastname: Parashar
authors.forename: Sara
authors.initials: S
authors.lastname: Upponi
authors.forename: Anne Y
authors.initials: AY
authors.lastname: Warren
authors.forename: Vincent J
authors.initials: VJ
authors.lastname: Gnanapragasam
authors.forename: Tim
authors.initials: T
authors.lastname: Eisen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology / Q000601:surgery*; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology / Q000601:surgery; D008207:Lymphatic Metastasis / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000379:methods*; D015588:Observer Variation; D011300:Preoperative Care / Q000379:methods*; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Kidney; lymphadenectomy; lymphadenopathy; renal carcinoma