title: Comparison of contrast-enhanced sonography with MRI in the diagnosis of complex cystic renal masses.
abstract: OBJECTIVE
  To compare the diagnostic performance of contrast-enhanced ultrasound (CEUS) with MRI for complex cystic renal masses.
  
  
  METHODS
  The study received approval from our Ethics Committee, and all subjects provided informed consent. Seventy-one complex cystic renal masses were assessed using CEUS and MRI in 59 patients (44 men and 15 women; age range, 21-78 years; mean age, 49.6 years). The masses were classified as malignant or benign based on the Bosniak classification system (benign, categories II and IIF; malignant, categories III and IV). The diagnostic performances of CEUS and MRI for complex cystic renal masses were compared with the final diagnosis in each case obtained by histopathology (n = 43) or imaging follow-up (n = 28).
  
  
  RESULTS
  Among 71 complex cystic renal masses, 35 were benign and 36 were malignant. The sensitivity, specificity, and overall accuracy of CEUS in assessing the masses were 97.2%, 71.4%, and 84.5% versus 80.6%, 77.1%, and 78.9% for MRI; the areas below the receiver operating characteristic curves of CEUS and MRI were 0.84 and 0.79, respectively. The agreement between the classification using CEUS and the final diagnoses was fair to good (κ = 0.70), and the agreement between MRI and the final diagnoses was also fair to good (κ = 0.58).
  
  
  CONCLUSIONS
  CEUS has higher diagnostic sensitivity and accuracy but lower specificity than MRI for classifying complex cystic renal masses. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43:203-209, 2015.
authors.affiliation: Department of Diagnostic Radiology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, No. 17 Panjiayuannanli Chaoyang District, Beijing, 100021, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Diagnostic Radiology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, No. 17 Panjiayuannanli Chaoyang District, Beijing, 100021, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Wu
authors.affiliation: Department of Ultrasound, Jinzhou Petrochemical Worker Hospital, No. 100 Jingyebeili Guta District, Jinzhou, 121001, China.
authors.forename: Tie
authors.initials: T
authors.lastname: Xue
authors.affiliation: Department of Diagnostic Radiology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, No. 17 Panjiayuannanli Chaoyang District, Beijing, 100021, China.
authors.forename: Yuzhi
authors.initials: Y
authors.lastname: Hao
authors.affiliation: Department of Diagnostic Radiology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, No. 17 Panjiayuannanli Chaoyang District, Beijing, 100021, China.
authors.forename: Jingrui
authors.initials: J
authors.lastname: Dai
keywords: Bosniak classification; MRI; contrast media; renal cell carcinoma; renal cyst; renal masses; ultrasonography