The patients underwent CT-guided radiofrequency ablation (RFA) at Wake Forest Baptist for kidney tumors ranging in size from 0.6 cm to 8.8 cm. A total of 125 tumors in 104 patients were treated over the period 2000 to 2006. In all of the patients, a biopsy had confirmed the presence of renal cell carcinomas (RCC), a common type of renal malignancy.
Of 95 tumors that were smaller than 3.7 cm (about 1.5 in.), all were completely eradicated by a single treatment, along with 14 of the larger tumors. Seven more of the 16 remaining larger tumors were eradicated after a second treatment, for a total 93 percent success rate for all 125 tumors. The results, reported in the August issue of the American Journal of Roentgenology, were based on follow-up exams over an average of about 14 months.
This is the largest treatment group to date of patients with biopsy-proven renal malignancies, said Ronald J. Zagoria, M.D., a professor of radiology at Wake Forest Baptist, an associate in urologic surgery, and lead author on the study. The results a high cure rate and low complication rate establish that at institutions with experience doing this procedure, this is an alternative method for treating small renal malignancies in patients who are not good surgical candidates.
RFA uses a needle-like treatment probe, guided by computed tomography (CT) as it is inserted through the skin into the tumor. The probes high-frequency alternating current heats the tumor tissue and destroys it. The technique has been used successfully in liver tumors since the early 1990s and has more recently been adapted for treatment of RCC.