LAPAROSCOPIC THERMAL ABLATION OF HEPATIC NEUROENDOCRINE TUMOR-METASTASES

Background. Neuroendocrine tumor metastases to the liver are generally slow growing but patients suffer from hormone hypersecretion despite aggressive multimodality therapy. A minimally invasive method of tumor ablation affords symptomatic improvement with minimal morbidity. Meth ods. Radiofrequency electrical energy is delivered to tissues via a 4- prong catheter resulting in tissue heating to 60 to 70 degrees C and c ell death. Porcine studies were conducted to define appropriate parame ter for energy delivery and then applied to patients using laparoscopi c techniques. Results. In the porcine model, 3.5 to 4 cm lesions were reproducibly created in 15 minutes using 30 to 50 W of power. The abla tion process was monitored via temperature feedback from thermocouples in the catheter tips and by a hyperechoic blush noted on ultrasonogra phy. Laparoscopic thermal ablation of 13 tumors in six patients with c arcinoid (two patients), gastrinoma, insulinoma, nonsecreting islet ce ll cancer, or medullary thyroid cancer was performed. There were no in traoperative complications, and all patients were discharged the next day. Successful oblation was confirmed by spiral-computed tomography a nd by symptomatic improvement In patients With secreting tumors. Concl usions. Laparoscopic thermal ablation of hepatic tumours is a novel, m inimally invasive method of providing effective cytoreduction of neuro endocrine tumors metastatic to the liver.