title: Incidence of multiple sporadic renal cell carcinomas in patients referred for renal radiofrequency ablation: implications for imaging follow-up.
abstract: OBJECTIVE
  The objective of our study was to report the incidence of multiple sporadic primary renal cell carcinomas (RCCs) in patients referred for radiofrequency ablation (RFA).
  
  
  METHODS
  A retrospective search identified 162 patients (104 men and 58 women; mean age, 74 years) without a history of von Hippel-Lindau disease with a total of 175 tumors treated with RFA for biopsy-proven primary renal malignancies at our institution from 1998 to 2009. Three groups of patients with multiple RCCs were identified: patients with a history of nephrectomy for RCC who had been referred for RFA of a new renal tumor, patients who presented with multiple renal tumors at the time of referral for RFA, and patients who were shown to have developed a new renal tumor on follow-up imaging after RFA.
  
  
  RESULTS
  Twenty-eight patients (17%) had multiple biopsy-proven RCCs. Eighteen patients (11%) had undergone prior nephrectomy for surgically proven RCC. The mean interval between prior nephrectomy and RFA referral was 122 months (range, 12-456 months). Seven patients (4%) without a history of nephrectomy presented with two biopsy-proven RCCs at RFA referral. Three patients (2%) who had not undergone nephrectomy and had a solitary RCC at the time of RFA had developed a new biopsy-proven RCC separate from the original treatment site on follow-up imaging after RFA. The mean time to diagnosis from the initial RFA treatment was 52 months (range, 25-89 months).
  
  
  CONCLUSIONS
  Imaging surveillance of patients referred for renal RFA may be important not only to assess treatment success but also to detect new RCCs.
authors.affiliation: Department of Diagnostic Imaging, The Alpert Medical School of Brown University/Rhode Island Hospital, 593 Eddy St, Providence, RI 02903, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Beland
authors.forename: Farrah J
authors.initials: FJ
authors.lastname: Wolf
authors.forename: David J
authors.initials: DJ
authors.lastname: Grand
authors.forename: Damian E
authors.initials: DE
authors.lastname: Dupuy
authors.forename: William W
authors.initials: WW
authors.lastname: Mayo-Smith
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D003287:Contrast Media; D005260:Female; D006801:Humans; D015994:Incidence; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy; D012086:Reoperation; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media