Bipolar radiofrequency ablation of liver tumors: technical experience and interval follow-up in 22 patients with 33 ablations.

ABSTRACT

INTRODUCTION: Bipolar radiofrequency ablation (BRFA) of hepatic tumors has short ablation times and may avoid convective heat loss from high-flow vessels. We evaluated the technical feasibility of and local recurrence following BRFA. METHODS: Twenty-two patients undergoing 33 laparoscopic BRFA were identified from September 2007 to April 2009. Lesion size, ablation times, morbidity, and pathologic presence of tumor after resection were evaluated. The ablation site recurrence rate is reported with median follow-up time of 24 months (range, 7-42). RESULTS: Ablation was performed for colorectal cancer hepatic metastases (CRCHM, n = 17), hepatocellular carcinoma (HCC, n = 2), gallbladder carcinoma (n = 2), or hepatic adenoma (n = 1). Mean lesion size was 3.6 ± 1.3 cm. Mean ablation time was 6.6 min, ±2 min, and there was no significant difference in ablation time for lesions <3 cm (5.5 ± 1.7 min) and those >3 cm (7 ± 2.9 min), P = 0.13. In each of five CRCHM patients who underwent staged hepatic resection, there was no histologic evidence of tumor in ablated areas. One ablation site recurrence occurred in the CRCHM group. CONCLUSION: BRFA achieves efficient ablation times using line of sight energy delivery. The short ablation times and the pathologic absence of viable tumor in post-BRFA resected specimens support further study of BRFA as a hepatic ablation method.