PERCUTANEOUS ULTRASOUND-GUIDED RADIOFREQUENCY ABLATION OF RECURRENT RENAL CELL CARCINOMA IN RENAL ALLOGRAFT AFTER PARTIAL NEPHRECTOMY LIEVEN GOEMAN, STEVEN JONIAU, RAYMOND OYEN, AND HEIN VAN POPPEL ABSTRACT Percutaneous thermal ablation is increasingly being studied in the treatment of renal tumors. Because radiofre- quency ablation is a minimally invasive and nephron-sparing procedure, it is ideally suited for patients with a single kidney, multiple tumors, or contraindications to conventional surgery. We report on a patient with recurrent renal cell carcinoma in a transplanted kidney that was successfully treated with percutaneous ultra- sound-guided radiofrequency ablation. UROLOGY 67: 199.e17–199.e19, 2006. © 2006 Elsevier Inc. M inimally invasive treatments for small renal cell carcinoma (RCC) are gaining popularity. The well-established surgical procedures, includ- ing open radical or partial nephrectomy and lapa- roscopic radical nephrectomy, can sometimes be too invasive in patients with a high risk of periop- erative morbidity. In situ ablation techniques, in- cluding radiofrequency ablation (RFA), have been developed and are now being explored as alterna- tive treatment options for select patient groups. CASE REPORT A 65-year-old woman had received a cadaver re- nal transplant in 1990. In 2001, an open surgical enucleation of a chromophobic RCC in the mid- pole of the graft was performed. The surgery was complicated because of extensive perirenal fibro- sis. The surgical margins were negative. At 2 years, follow-up ultrasonography of the transplant re- vealed a 15  20  15-mm solid mass in the upper pole. Magnetic resonance imaging confirmed these findings and showed similar radiologic character- istics to the lesion resected 2 years earlier (Fig. 1). No evidence of distant metastases was found. Be- cause of the rather poor general condition and the difficulty of the first operation, the patient was not considered a suitable candidate for repeated sur- gery. It was decided that percutaneous ultrasound- guided RFA of the lesion would be performed. No bowel loops were adjacent to the upper pole. A Cool-tip(r) radiofrequency needle (Radionics, Burlington, Mass) was advanced into the tumor under ultrasound guidance. The tumor was ablated for 12 minutes. At the end of the procedure, the core temperature in the ablation zone had reached 80°C. The needle tract was ablated during with- drawal of the needle tip. The procedure was well tolerated. The patient was discharged the day after the procedure. Her renal function remained un- changed. A follow-up contrast-enhanced ultra- sound scan at 6 months revealed no contrast en- hancement in the lesion (Fig. 2). Therefore, the procedure was considered successful. COMMENT Compared with the general population, trans- plant recipients are at increased risk of cancer. It has been shown that in posttransplant patients, RCC of the native kidneys occurs more frequently than in the general population. RCC arising in a transplanted kidney is extremely rare. Only 25 cases have been reported in the Cincinnati Trans- plant Tumor Registry (1995 data). 1 In the present case, RCC developed in a renal transplant 11 years after transplantation. To our knowledge, this is longer than any previously re- ported delay between renal transplantation and the development of an allograft RCC. In published studies, the mean interval from transplantation to the appearance of RCC was 3.5 years. 1,2 The options for treatment of renal transplant From the Departments of Urology and Radiology, UZ Gasthuis- berg, Leuven, Belgium Address for correspondence: Hein Van Poppel, M.D., Ph.D., Department of Urology, UZ Leuven, Herestraat 49, 3000 Leuven, Belgium. E-mail: Hendrik.VanPoppel@uz.kuleuven.ac.be Submitted: April 5, 2005, accepted (with revisions): July 22, 2005 CASE REPORT © 2006 ELSEVIER INC. 0090-4295/06/$32.00 ALL RIGHTS RESERVED doi:10.1016/j.urology.2005.07.039 199.e17