[Radiofrequency ablation of liver metastases. Technique and initial results]

Primary and secondary malignant hepatic tumors are the most common tumors with a much more higher incidence of hepatic metastases. Chemotherapy and radiation therapy are in general ineffective. Therefore, surgical resection is considered the method of choice in the treatment of malignant hepatic lesions. Due to systemic disease, general medical or procedure-related reasons hindering surgery, only 25 to 45% of the patients with metastatic disease of the liver are suitable for a curative surgical therapy. In resectable lesions thermoablative methods can offer an alternative to the surgical therapy. The most experience exists in radiofrequency ablation techniques. Technique, indications, contraindications, and limitations of the radiofrequency ablation will be discussed together with a presentation of own cases and a review of the literature. In 37 patients the primary technical success rate of the ablation was 97.3% (72 of 74 lesions). In 4 cases a hematoma of the liver capsule occurred. One of these had to be treated interventionally. During the limited follow-up period of 9 months no local recurrency was seen, however 4 patients developed new hepatic metastases. Beside differences in practicability it is not yet clarified if there are differences in the therapeutic efficacy of the different thermoablation methods. Nevertheless, the results of the ablation therapy may parallel the results of the surgical resection. Interstitial thermotherapy can provide a valuable contribution to local tumor control. However, the final significance of the thermoablation techniques within oncological therapy regimens has to be evaluated in further multidisciplinary studies.