title: Percutaneous cryoablation of anterior renal masses: technique, efficacy, and safety.
abstract: OBJECTIVE
  The safety and efficacy of renal tumor ablation are related, in part, to tumor location. Anterior tumors present a challenge due to the risk of injury to adjacent structures. The purpose of this study was to review the techniques, complications, and short-term outcomes of percutaneous cryoablation of anterior renal masses at a single institution.
  
  
  METHODS
  We retrospectively identified the cases of 35 patients with 38 anterior renal masses managed with percutaneous imaging-guided cryoablation of renal tumors from March 2003 through February 2009. The technical success of the ablation procedure, serious complications, and evidence of local tumor recurrence were evaluated for each patient.
  
  
  RESULTS
  The average maximal diameter of the anterior renal masses was 2.9 cm (SD, 0.9 cm; range, 1.4-4.8 cm). A single cryoablation procedure was performed for treatment of each patient, and technically successful ablation was achieved for all 38 tumors. A single severe adverse event occurred in one of the 35 patients (3% major complication rate). This patient had a pulmonary embolism (diagnosed at CT angiography the day after ablation). He recovered and was discharged from the hospital with anticoagulant medication only 2 days after the procedure. No local tumor recurrence was identified in any of the 29 patients who underwent follow-up contrast-enhanced CT or MRI with images available for review 3 months or longer from the time of ablation (mean, 18 months; range, 3-45 months).
  
  
  CONCLUSIONS
  Percutaneous cryoablation of anterior renal masses can be performed with high technical success and low complication rates. The lack of local renal tumor recurrence at short-term follow-up evaluation in this study is encouraging, but long-term follow-up is necessary to ensure the durability of treatment.
authors.affiliation: Department of Radiology, Mayo Clinic, 200 1st St. SW, Rochester, MN 55905, USA.
authors.forename: Grant D
authors.initials: GD
authors.lastname: Schmit
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Atwell
authors.forename: Bradley C
authors.initials: BC
authors.lastname: Leibovich
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Callstrom
authors.forename: Anil N
authors.initials: AN
authors.lastname: Kurup
authors.forename: David A
authors.initials: DA
authors.lastname: Woodrum
authors.forename: J William
authors.initials: JW
authors.lastname: Charboneau
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000601:surgery*; D003452:Cryosurgery / Q000379:methods*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011183:Postoperative Complications / Q000175:diagnosis; D012189:Retrospective Studies; D012449:Safety; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome