Efficacy of percutaneous radiofrequency ablation may vary with clear cell renal cell cancer histologic subtype.

McClure, Timothy; Pantuck, Allan; Sayer, James; Raman, Steven

PURPOSE The purpose of the study is to determine if clear cell renal cell cancer (RCC) subtype predicts efficacy in percutaneous radiofrequency (RF) ablation of RCC. METHODS AND MATERIALS Patients who underwent percutaneous RF ablation for histologically proven RCC subtypes were retrospectively reviewed. Group comparisons were done using univariate and multivariate logistic regression analysis to determine factors impacting primary, secondary, and total technique effectiveness. A p value less than 0.05 was considered significant. RESULTS One hundred pathologically proven RCC lesions in 84 patients were analyzed. The median (mean) follow-up was 24 (27) months (range 1-106 months). Overall RF ablation primary, secondary and total technique effectiveness was 86%, 9%, and 95%, respectively. Clear cell subtype demonstrated worse treatment efficacy with primary, secondary, and total technique effectiveness of 42/55 (76.4%), 8/55 (14.5%), and 50/55 (90.9%), respectively. Non-clear cell subtypes had primary, secondary, and total technique effectiveness of 44/45(97.8%), 1/45 (2.2%), 45/45 (100%), respectively. The difference in primary (p = 0.002), secondary (p = 0.032), and total (p = 0.038) technique effectiveness between the two groups was statistically significant. CONCLUSION Clear cell RCC was a novel predictor of primary, secondary, and total technique efficacy in the percutaneous RF ablation of clear cell RCC.