title: Prospective evaluation of MRI, ¹¹C-acetate PET/CT and contrast-enhanced CT for staging of bladder cancer.
abstract: OBJECTIVE
  To prospectively evaluate the diagnostic performance of magnetic resonance imaging (MRI), (11)C-acetate positron emission tomography/computed tomography (PET/CT) and contrast-enhanced CT for bladder cancer staging, using whole-mount pathologic review of radical cystectomy and pelvic lymph node specimens as the reference standard.
  
  
  METHODS
  The institutional review board approved this prospective study, which was compliant with the Health Insurance Portability and Accountability Act. Written informed consent was obtained from 16 patients with histologically confirmed bladder cancer who underwent MRI, (11)C-acetate PET/CT and contrast-enhanced CT before radical cystectomy and pelvic lymph node dissection. Before imaging 4/16 patients had received intravesical Bacillus Calmette-Guérin treatment, 6 had received systemic chemotherapy, 3 had received both and 3 had received neither. Measures of diagnostic performance including accuracy, sensitivity and specificity were estimated separately for each imaging modality.
  
  
  RESULTS
  MRI correctly staged 56% of patients (9/16), overstaged 38% (6/16) and understaged 6% (1/16). CT correctly staged 50% of patients (8/16), overstaged 44% (7/16) and understaged 6% (1/16). In 9 patients, (11)C-acetate PET/CT showed uptake within the bladder wall; the uptake was true-positive in 7 patients and false-positive in 2 patients. Of the remaining 7 patients, 5 had true-negative and 2 had false-negative PET/CT results for cancer in the bladder wall. For all modalities, staging accuracy was reduced in patients with a history of prior intravesical and/or systemic chemotherapy.
  
  
  CONCLUSIONS
  In staging bladder cancer, MRI, (11)C-acetate PET/CT and CT displayed similar levels of accuracy. For all modalities, a history of intravesical and/or systemic chemotherapy affected staging accuracy.
authors.affiliation: Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States. vargasah@mskcc.org
authors.forename: H A
authors.initials: HA
authors.lastname: Vargas
authors.forename: O
authors.initials: O
authors.lastname: Akin
authors.forename: H
authors.initials: H
authors.lastname: Schöder
authors.forename: S
authors.initials: S
authors.lastname: Olgac
authors.forename: G
authors.initials: G
authors.lastname: Dalbagni
authors.forename: H
authors.initials: H
authors.lastname: Hricak
authors.forename: B H
authors.initials: BH
authors.lastname: Bochner
mesh_terms: D000085:Acetates; D000328:Adult; D000368:Aged; D002244:Carbon; D003287:Contrast Media; D005260:Female; D006801:Humans; D007472:Iohexol; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D009367:Neoplasm Staging / Q000379:methods; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis*
chemical_list: D000085:Acetates; D003287:Contrast Media; D019275:Radiopharmaceuticals; C438206:carbon-11 acetate; D007472:Iohexol; D002244:Carbon