title: Clinical sequelae of radiographic iceball involvement of collecting system during computed tomography-guided percutaneous renal tumor cryoablation.
abstract: OBJECTIVE
  Percutaneous renal tumor cryoablation is being evaluated as a treatment option for small renal tumors. However, when tumors are located centrally, involvement of the collecting system by the radiographic iceball can occur. We reviewed our series of computed tomography (CT)-guided percutaneous renal tumor cryoablation to identify those cases in which there appeared to be involvement of the collecting system by the radiographic iceball and to determine any clinical sequelae of such involvement.
  
  
  METHODS
  Retrospective review of the medical records identified 6 patients who had undergone CT-guided percutaneous renal tumor cryoablation with evidence of collecting system involvement. Measurements of the tumor size, size of the radiographic iceball, and the size of the immediate postprocedure "cryozone" (region of apparent treatment on contrast-enhanced CT) were obtained from the preprocedure, intraprocedure, and immediate postprocedure CT scans. Follow-up imaging was obtained beginning at 3 to 6 months.
  
  
  RESULTS
  Six patients were identified who met the inclusion criteria and had at least 3 months of documented follow-up. Despite the apparent involvement of the collecting system during the cryoablation procedure, no patient developed clinical signs or symptoms or radiographic evidence of a urine leak or fistula formation. Furthermore, no evidence of ureteral narrowing or stricture formation has been found to date, with a mean follow-up of 167.7 days (range 90 to 288).
  
  
  CONCLUSIONS
  We observed no clinically appreciable urine leaks despite what appeared to be obvious involvement of the collecting system by the radiographic iceball. However, care should be exercised to avoid this insult when possible until additional research has confirmed its safety.
authors.affiliation: James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Baltimore, Maryland 21287, USA. chris.warlick@jhmi.edu
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Warlick
authors.forename: Guilherme C
authors.initials: GC
authors.lastname: Lima
authors.forename: Mohamad E
authors.initials: ME
authors.lastname: Allaf
authors.forename: Ioannis
authors.initials: I
authors.lastname: Varkarakis
authors.forename: Sompol
authors.initials: S
authors.lastname: Permpongkosol
authors.forename: Edward M
authors.initials: EM
authors.lastname: Schaeffer
authors.forename: Louis R
authors.initials: LR
authors.lastname: Kavoussi
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Jarrett
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Solomon
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging / Q000628:therapy*; D003452:Cryosurgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging / Q000628:therapy*; D007685:Kidney Tubules, Collecting / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted; D014057:Tomography, X-Ray Computed