title: Malignant renal cysts: diagnostic performance and strong predictors at MDCT.
abstract: BACKGROUND
  Utilization of multidetector-row CT (MDCT) is anticipated to improve the diagnostic accuracy and reliability for determining malignant cysts.
  
  
  OBJECTIVE
  To assess the diagnostic accuracy, interobserver agreement, benefit of consensus reading, and strong predictors of malignancy in determining malignant cystic renal masses at MDCT.
  
  
  METHODS
  Two radiologists independently rated the probability of malignancy at MDCT in 72 benign and 53 malignant cysts. The accuracy and interobserver agreement for determining malignant cysts were evaluated. The strong predictors of malignancy were determined, and in patients with interobserver disagreement for determining malignant cysts, consensus readings were performed.
  
  
  RESULTS
  Az value of the two readers was 0.905-0.936 and the sensitivity and specificity were 85-89% and 83-93%, respectively. The overall interobserver agreement for determining the malignant cyst was good as the kappa value was 0.696 (% agreement, 61% (76/125)). Thickened irregular wall, thickened irregular septa, and enhancing soft tissue component were strong predictors for malignancy with both readers. In the 17 patients with interobserver disagreement for determining malignant cysts, the sensitivity was improved from 38-63% to 89% by the consensus reading.
  
  
  CONCLUSIONS
  At MDCT, some false negative decisions for determining malignant cysts can be corrected by consensus reading, and thickened irregular septa, thickened irregular wall, and enhancing soft tissue component are the strong predictors of malignant cysts.
authors.affiliation: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan, Seoul, 138-736, Korea.
authors.forename: Dae Yoon
authors.initials: DY
authors.lastname: Kim
authors.forename: Jeong Kon
authors.initials: JK
authors.lastname: Kim
authors.forename: Gyeong-Eun
authors.initials: GE
authors.lastname: Min
authors.forename: Han-Jong
authors.initials: HJ
authors.lastname: Ahn
authors.forename: Kyoung-Sik
authors.initials: KS
authors.lastname: Cho
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D006801:Humans; D007472:Iohexol / Q000031:analogs & derivatives; D007479:Iopamidol; D052177:Kidney Diseases, Cystic / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide; D007479:Iopamidol