Intraoperative microwave tissue coagulation as treatment for patients with nonresectable hepatocellular carcinoma

Background. The microwave tissue coagulator (2450 MHz) has been used clinically in the treatment of hepatocellular carcinoma (HCC) to transection of the liver parenchyma and has proven an excellent method for hemostasis. There are, however, few reports on the application of this coagulator to the induction of tumor necrosis. Methods. Microwave tissue coagulation (MTC) was applied at laparotomy in eight patients with nonresectable multiple HCCs. All patients were treated with a combination of resection or intrahepato-arterial chemotherapy and MTC. A total of 222 bouts of MTC were applied to 21 tumors, the largest of which was 65 mm in largest dimension. The monopolar needle electrode was inserted directly into the tumor and the procedure was repeated at approximately 5 mm intervals. Results. Levels of alpha-fetoprotein in serum were found to have decreased in all patients one month after surgery with MTC. Contrast-enhanced computerized tomography (CT) showed the complete absence of blood flow in all tumors subjected to MTC. Needle biopsy one month after MTC confirmed tumor necrosis in all cases. All patients are alive at the time of this report, with the longest survival period being 24 months. In three of eight patients, new tumors were confirmed by angiographic CT at sites separate from the treated tumors. MTC resulted in fewer adverse effects on liver function and less extensive inflammatory reactions than liver resection. Conclusion. Intraoperative MTC appears to be an effective method for inducing local tumor necrosis, and may be of use in combination with palliative surgery for multiple HCC when radical liver resection is not feasible.