title: Multilocular cystic renal cell carcinoma: clinicopathological features and preoperative prediction using multiphase computed tomography.
abstract: OBJECTIVE
  • To analyse the clinicopathological and radiological features of multilocular cystic renal cell carcinoma (MCRCC) and to determine the preoperative factors differentiating MCRCC from other cystic RCC (CRCC).
  
  
  METHODS
  • The medical records of 53 patients with complex cystic renal masses evaluated by multiphase computed tomography (CT), surgically removed and confirmed as sporadic RCC were reviewed. • Of these 53 patients, 23 were classified as having MCRCC and 30 as other CRCCs, defined as RCCs with extensive cystic change or cystic necrosis. • Another 22 patients were treated for complex cystic renal masses presumed to be RCC and diagnosed as having benign cyst.
  
  
  RESULTS
  • Benign cysts and MCRCCs were significantly more likely to be of Bosniak classification III than other CRCCs (77% vs 61% vs 27%, P= 0.001). • The mean Hounsfield unit (HU) during the corticomedullary phase (CMP) was significantly higher in other CRCCs, with HU ≥38 having 83% sensitivity and 80% specificity for predicting other CRCCs. • In a multiple regression model, Bosniak classification and mean HU during CMP were independent factors predictive of other CRCCs. • In the 41 patients with masses >4 cm in diameter, the combination of Bosniak classification IV and HU ≥38 during CMP showed 63% sensitivity, 96% specificity, 91% positive predictive value and 80% negative predictive value, yielding 2% false-positive and 15% false-negative rates.
  
  
  CONCLUSIONS
  • The mean HU during CMP and Bosniak classification can differentiate MCRCC from other CRCCs. • This could help in selecting an appropriate surgical method, such as nephron-sparing surgery, for complex cystic renal masses >4 cm.
authors: Department of Urology, Radiology Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors: Dalsan
authors: D
authors: You
authors: Myungsun
authors: M
authors: Shim
authors: In Gab
authors: IG
authors: Jeong
authors: Cheryn
authors: C
authors: Song
authors: Jeong Kon
authors: JK
authors: Kim
authors: Jae Y
authors: JY
authors: Ro
authors: Jun Hyuk
authors: JH
authors: Hong
authors: Hanjong
authors: H
authors: Ahn
authors: Choung-Soo
authors: CS
authors: Kim
mesh_terms: D000328:Adult; D000368:Aged; D002292:Carcinoma, Renal Cell / Q000145:classification / Q000000981:diagnostic imaging* / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D052177:Kidney Diseases, Cystic / Q000145:classification / Q000000981:diagnostic imaging* / Q000473:pathology; D007680:Kidney Neoplasms / Q000145:classification / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*