Percutaneous imaging-guided radiofrequency ablation of small renal cell carcinoma: techniques and outcomes of 24 treatment sessions in 18 consecutive patients.

PURPOSE To evaluate the early clinical experience associated with percutaneous imaging-guided radiofrequency ablation (RFA) in patients with renal cell carcinoma (RCC). METHODS Eighteen consecutive patients with RCC were treated with percutaneous RFA sessions (24 sessions for 19 solitary RCC in 18 patients: 15 patients underwent a single RFA session, 3 had 2 sessions and one 3 sessions). Treatment indications were localized, solid renal mass <4.5 cm, comorbidities precluding surgery, high operation risk, and refusal to perform surgery. During 23 sessions, RFA was performed using computed tomography (CT) guidance and in one session it was guided by ultrasonography. The average patient age was 76.8±7.6 years (range 64-89), and the average renal mass size 3.3 ±0.7 cm (range 2.0-4.5). Follow-up imaging was performed at 3- and 6-month intervals and yearly thereafter. Successful treatment was defined as lack of enhancement of the treated region on follow-up CT studies. RESULTS RFA was technically successful in all patients. After the last imaging control, 17 of the 19 tumors were completely necrotic according to the imaging criteria (the secondary clinical success rate was 89.5%). Thirteen tumors were not visible on the first follow-up imaging control (the primary clinical success rate was 68.4% - 13 of 19). In 4 of the 6 patients residual tumors were successfully re-ablated, while in 2 patients repeated RFAs were not performed at the time of writing this report. Five patients (20.8%) developed treatmentrelated complications, including mild pain, large perirenal abscess, mild perirenal hematoma and transient elevation of the white blood cell count. The mean follow-up period was 25.3±16.8 months (range 1-51). CONCLUSION RFA is effective and safe treatment option of exophytic RCC <5 cm in diameter in patients not suitable for surgery due to serious concomitant diseases or advanced age.