Radio Frequency Ablation of Small Renal Tumors: Intermediate Results
- 1 May 2004
- journal article
- clinical trial
- Published by Ovid Technologies (Wolters Kluwer Health) in Journal of Urology
- Vol. 171 (5), 1814-1818
- https://doi.org/10.1097/01.ju.0000119905.72574.de
Abstract
Purpose: With evolving radio frequency technology, the clinical application of radio frequency ablation (RFA) has been actively investigated in the treatment for small renal tumors. We present our intermediate patient outcomes after RFA. Materials and Methods: Since January 2001, 17 patients with a total of 24 hereditary renal tumors ranging from 1.2 to 2.85 cm were treated with RFA using the 200 W Cool-tip RF System (Radionics, Burlington, Massachusetts) under laparoscopic (9) or percutaneous (8) guidance and had a minimum 1-year followup. A percutaneous approach was considered unsuitable if kidney tumors were contiguous to bowel, ureter or large vessels. Treatment eligibility criteria included an average tumor diameter of less than 3.0 cm, tumor growth during 1 year and solid appearance with contrast enhancement (HU change greater than 20) on computerized tomography (CT). Postoperative followup consisted of CT with and without intravenous contrast, and renal function assessment at regular intervals. Results: Median patient age was 38 years (range 20 to 51). At a median followup of 385 days (range 342 to 691), median tumor or thermal lesion diameter decreased from 2.26 to 1.62 cm (p = 0.0013), and only 1 lesion (4%), which was located centrally near the hilum, exhibited contrast enhancement (HU change greater than 10) on CT at 12 months. Of the 15 renal tumors ablated laparoscopically, 13 were in direct contact with the bowel and 2 were abutting the ureter, necessitating mobilization before RFA. Laparoscopic ultrasound was used to guide radio frequency electrode placement and monitor the ablation process in these cases. Operative time and intraoperative blood loss (mean ± standard mean of error) were 243 ± 29 minutes and 67 ± 9 cc, respectively. In 1 patient whose ureter was adherent to the tumor a ureteropelvic junction obstruction developed after laparoscopic RFA, requiring open repair. Conclusions: At the minimum 1-year followup 23 of 24 ablated tumors lacked contrast uptake on CT, meeting our radiographic criteria of successful RFA treatment. RFA treatment of small renal tumors using the Radionics system appears to result in superior treatment outcomes compared to those of earlier series with lower radio frequency power generators. A high wattage generator might attain more consistent energy deposition with subsequent cell death in the targeted tissue due to less convective heat loss.Keywords
This publication has 19 references indexed in Scilit:
- Laparoscopic Application Of Radio Frequency Energy Enables In Situ Renal Tumor Ablation And Partial NephrectomyJournal of Urology, 2003
- Phase II Trial of Radio Frequency Ablation of Renal Cancer: Evaluation of the Kill ZoneJournal of Urology, 2002
- Incomplete Renal Tumor Destruction Using Radio Frequency Interstitial AblationJournal of Urology, 2002
- Radio Frequency Ablation of Renal Cell Carcinoma: Preliminary Clinical ExperienceJournal of Urology, 2002
- Radio Frequency Ablation of Renal Cell Carcinoma: Preliminary Clinical ExperienceJournal of Urology, 2002
- The Uncertainty Of Radio Frequency Treatment Of Renal Cell Carcinoma: Findings At Immediate And Delayed NephrectomyJournal of Urology, 2002
- DEVELOPMENT OF A RADIOFREQUENCY BASED THERMAL THERAPY TECHNIQUE IN AN IN VIVO PORCINE MODEL FOR THE TREATMENT OF SMALL RENAL MASSESJournal of Urology, 2001
- Incidental renal cell carcinoma—age and stage characterization and clinical implications: study of 1092 patients (1982–1997)Urology, 2000
- Radiofrequency Interstitial Tumor Ablation (RITA) Is a Possible New Modality for Treatment of Renal Cancer: Ex Vivo and in Vivo ExperienceJournal of Endourology, 1997
- Percutaneous RF interstitial thermal ablation in the treatment of hepatic cancer.American Journal of Roentgenology, 1996