title: Preoperative decision making for renal cell carcinoma: cystic morphology in cross-sectional imaging might predict lower malignant potential.
abstract: OBJECTIVE
  Several histologic studies showed more favorable oncologic outcome for renal cell carcinoma (RCC) with cystic change. However, there is no prognostic tool to judge on cystic RCC preoperatively. We hypothesized, that cystic morphology in cross-sectional imaging predicts lower malignant potential.
  
  
  METHODS
  From our prospectively conducted oncologic database, we identified 825 patients who underwent surgery for malignant renal tumors between 2001 and 2010. In 348 cases (42%), adequate imaging was available for an independent review by 2 radiologists. We excluded recurrent and synchronous bilateral RCC, familial syndromes, collecting duct carcinoma, and metastases of other origin. For the resulting 319 patients, we compared clinical, pathologic, and survival outcomes.
  
  
  RESULTS
  Median age was 63 (19-88) years and 220 (69%) patients were male. Median follow-up was 1.7 (0-9.8) years. Of 319 renal masses, 277 (86.8%) were solid and 42 (13.2%) were cystic. In cystic RCC, median tumor diameter was lower (3 cm vs. 4 cm, P = 0.002) and nephron-sparing surgery was more frequent (69% vs. 41.5%, P = 0.002). None of the patients with cystic RCC and 56 (20.2%) with solid RCC had synchronous systemic disease (P = 0.001). The nuclear grade of cystic RCC was more favorable (P = 0.002). Patients with cystic RCC showed better overall (P = 0.049) and cancer-specific survival (P = 0.027). In a multivariate model, only synchronous metastases, positive R status, and greater tumor diameter were independent risk factors (P ≤ 0.03).
  
  
  CONCLUSIONS
  We report the first study to show that cystic morphology in cross-sectional imaging might predict RCC with a lower malignant potential. This insight could allow less invasive treatment strategies in selected patients.
authors.affiliation: Department of Urology, University of Heidelberg, Heidelberg, Germany. Electronic address: johannes.huber@uniklinikum-dresden.de.
authors.forename: Johannes
authors.initials: J
authors.lastname: Huber
authors.affiliation: Department of Urology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Winkler
authors.affiliation: Department of Urology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Hildegard
authors.initials: H
authors.lastname: Jakobi
authors.affiliation: Institute for Medical Biometrics and Informatics, University of Heidelberg, Heidelberg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bruckner
authors.affiliation: Institute of Pathology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Wilfried
authors.initials: W
authors.lastname: Roth
authors.affiliation: Department of Diagnostic and Interventional Radiology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Hallscheidt
authors.affiliation: Department of Diagnostic and Interventional Radiology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Keivan
authors.initials: K
authors.lastname: Daneshvar
authors.affiliation: Department of Urology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Hohenfellner
authors.affiliation: Department of Urology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Pahernik
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D003657:Decision Making; D003952:Diagnostic Imaging; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy; D015588:Observer Variation; D057234:Preoperative Period; D011379:Prognosis; D011871:Radiology; D016896:Treatment Outcome; D055815:Young Adult
keywords: Decision making; Imaging; Prognosis; Renal cell carcinoma