title: Imaging-guided percutaneous radiofrequency ablation of solid renal masses: techniques and outcomes of 38 treatment sessions in 32 consecutive patients.
abstract: OBJECTIVE
  The purpose of this study was to describe the treatment techniques and results of 38 consecutive imaging-guided percutaneous radiofrequency ablations of solid renal masses performed in 32 patients.
  
  
  METHODS
  Solid renal masses in 32 patients underwent 38 treatment sessions using imaging-guided percutaneous radiofrequency ablation. During 36 sessions, radiofrequency ablation was performed using CT guidance, and two, using sonographic guidance. The average patient age was 76 years (range, 52-87 years), and the average renal mass size was 2.6 cm (range, 1-5 cm). The average number of radiofrequency treatments per solid mass at each session was 2.4 (range, 1-6 treatments), and the average time per treatment was 9.2 min (range, 3-14 min). A single electrode was used in 12 sessions, and a cluster electrode was used in 26 sessions. The average follow-up time was 9 months (range, 1-36 months).
  
  
  RESULTS
  Twenty-six of 32 patients had successful treatment of the solid renal mass using percutaneous imaging-guided radiofrequency ablation after one treatment session. Successful treatment was defined as lack of enhancement of the treated region on follow-up CT. Six of 32 patients had residual enhancing tissue after the first treatment session and returned for a second session. Five of these six retreatments were successful. Masses requiring a second treatment session were significantly larger than masses treated in a single session (3.5 vs 2.4 cm, respectively; p = 0.0013). Two patients had perinephric hematomas (which did not require transfusion), and one patient developed a 5-mm skin metastasis at the electrode insertion site, which was resected without recurrence.
  
  
  CONCLUSIONS
  Percutaneous imaging-guided radiofrequency ablation shows promise in the treatment of solid renal malignancies.
authors.affiliation: Department of Diagnostic Imaging, Rhode Island Hospital, Brown Medical School, 593 Eddy St., Providence 02903, USA.
authors.forename: William W
authors.initials: WW
authors.lastname: Mayo-Smith
authors.forename: Damian E
authors.initials: DE
authors.lastname: Dupuy
authors.forename: Pranay M
authors.initials: PM
authors.lastname: Parikh
authors.forename: John A
authors.initials: JA
authors.lastname: Pezzullo
authors.forename: John J
authors.initials: JJ
authors.lastname: Cronan
mesh_terms: D018249:Adenoma, Oxyphilic / Q000000981:diagnostic imaging* / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D018207:Angiomyolipoma / Q000000981:diagnostic imaging* / Q000601:surgery*; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging* / Q000601:surgery*; D017115:Catheter Ablation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography