title: Diagnostic efficacy of [11C]choline positron emission tomography/computed tomography compared with conventional computed tomography in lymph node staging of patients with bladder cancer prior to radical cystectomy.
abstract: BACKGROUND
  Current imaging techniques are of limited value for lymph node (LN) staging in bladder cancer (BCa) patients scheduled for radical cystectomy (RC).
  
  
  OBJECTIVE
  Evaluate the diagnostic efficacy of [11C]choline positron emission tomography in combination with computed tomography (PET/CT) for LN staging of patients with BCa scheduled for RC and compare that efficacy with the diagnostic efficacy of CT and the gold standard of histopathologic evaluation.
  
  
  METHODS
  From June 2004 to May 2007, 44 patients with localized BCa were staged with [11C]choline PET with low-dose CT for attenuation correction and simultaneous intravenous and rectal contrast-enhanced diagnostic CT before RC and pelvic lymph node dissection (PLND). LNs were dissected from the internal and external iliac arteries up to the origin of the inferior mesentery artery according to a template with 14 predefined anatomic fields.
  
  
  METHODS
  Diagnostic [11C]choline PET/CT before RC and regional LN dissection.
  
  
  METHODS
  Histopathologic findings of resected LN were correlated with the results of [11C]choline PET/CT and CT alone in a patient- and field-based manner. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of [11C]choline PET/CT and CT were assessed.
  
  
  CONCLUSIONS
  LN metastases were found in 12 of 44 patients (27%). On patient-based analysis, sensitivity, specificity, PPV, NPV, and accuracy for [11C]choline PET/CT were calculated as 58%, 66%, 39%, 81%, and 64%, respectively; and for CT the calculated percentages were 75%, 56%, 39%, 86%, and 61%, respectively. Twenty-five of 471 dissected LN fields (5%) showed metastases. On field-based analysis, sensitivity, specificity, PPV, NPV, and accuracy for [11C]choline PET/CT were 28%, 95%, 21%, 96%, and 91%, respectively; for CT, the calculated percentages were 39%, 92%, 20%, 96%, and 90%, respectively. Limitations of this study are small patient number and the fact that not all patients underwent extensive PLND.
  
  
  CONCLUSIONS
  In patients with BCa who were scheduled for RC, preoperative LN staging with [11C]choline PET/CT was not able to improve diagnostic efficacy compared with conventional CT alone.
authors.affiliation: Department of Urology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany. t.maurer@lrz.tum.de
authors.forename: Tobias
authors.initials: T
authors.lastname: Maurer
authors.forename: Michael
authors.initials: M
authors.lastname: Souvatzoglou
authors.forename: Hubert
authors.initials: H
authors.lastname: Kübler
authors.forename: Katharina
authors.initials: K
authors.lastname: Opercan
authors.forename: Stefan
authors.initials: S
authors.lastname: Schmidt
authors.forename: Ken
authors.initials: K
authors.lastname: Herrmann
authors.forename: Jens
authors.initials: J
authors.lastname: Stollfuss
authors.forename: Gregor
authors.initials: G
authors.lastname: Weirich
authors.forename: Bernhard
authors.initials: B
authors.lastname: Haller
authors.forename: Jürgen E
authors.initials: JE
authors.lastname: Gschwend
authors.forename: Markus
authors.initials: M
authors.lastname: Schwaiger
authors.forename: Bernd J
authors.initials: BJ
authors.lastname: Krause
authors.forename: Uwe
authors.initials: U
authors.lastname: Treiber
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002250:Carbon Radioisotopes; D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000601:surgery; D002794:Choline; D015653:Cystectomy / Q000379:methods; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D049268:Positron-Emission Tomography; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D001749:Urinary Bladder Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery
chemical_list: D002250:Carbon Radioisotopes; D002794:Choline