Percutaneous ultrasound-guided radiofrequency ablation (RFA) using saline-perfused (wet) needle electrodes for the treatment of hepatocellular carcinoma--long term experience.

PURPOSE: For many reasons, resection of hepatocellular cancer (HCC) is not feasible in most cases. Radiofrequency (RFA) ablation has proven to be an effective minimally invasive alternative. It has been shown in ex vivo and animal trials that needle applicators perfused with isotonic saline solution could be an effective approach to enlarging the coagulation zone. However, long term survival data for the treatment of HCC are not yet available.

MATERIALS AND METHODS: 37 patients with a total of 64 histologically proven HCC with a maximum of 3 tumors of up to 6 cm and a contraindication to partial liver resection or orthotopic liver transplantation were treated with the Integra HiTT106 using wet monopolar single, wet bipolar double or wet triple needle electrodes. The mean HCC size was 37.7 mm (range 15 to 60 mm). Follow-up examinations were performed 2 days and 1, 3, 6, 9 months after RFA and every 6 months thereafter. The survival rate was calculated from the time of the first RFA session.

RESULTS: 1, 2 and 5-year survival was 24/32 (75%), 14/31 (45%) and 3/21 (14%) overall; 18/19 (95%), 12/18 (67%) and 3/10 (30%) for HCC Child A; and 6/13 (46%), 2/13 (15%) and 0/11 (0%), for HCC Child B. Complete remission was achieved in 86.5 % of the patients (total: 32 out of 37, multi-needle 18 / 21, single needle 14 / 16). Distant recurrence occurred overall in 20 out of 37 patients (54%), including 9 of 21 treated with multiple needles (43% of patients) and 11 of the 16 patients treated with a single electrode (69%). The overall complication rate was 10.8%. Local recurrence was found for tumors measuring 3 cm-5 cm (n=28) in 7 out of 13 cases after single electrode RFA and in 1 out of 15 after multiple electrode treatment (significant, p=0.009). No significant difference between the single and multi-needle group was found for tumors >5 cm and <3 cm.

CONCLUSION: RFA using multiple wet electrodes shows promise as an effective method for treating inoperable HCC especially in cases with well-preserved liver function. Multiple electrodes seem to be superior to single electrodes with respect to the local recurrence rate for tumors between 3 and 5 cm.