Ultrasound-guided percutaneous thermal and non-thermal ablation of intrahepatic cholangiocarcinoma

Abstract

Ultrasound-guided percutaneous thermal ablation has gained popularity as treatment for malignant hepatic tumors. It was first introduced as ablation therapy for hepatocellular carcinoma and cirrhosis comorbidity. Recently, this technique has also been used in the treatment of intrahepatic cholangiocarcinoma for patients who are not eligible for surgical resection. There are several types of thermal ablation techniques. Radiofrequency ablation and microwave ablation are two common methods that induce necrosis of the lesions. Irreversible electroporation is a relatively new non-thermal technique and is suitable in cases where thermal ablation would be ineffective or dangerous (e.g., malignant tumors close to vascular or biliary structures). Irreversible electroporation can induce tumoral necrosis without damage to vascular and biliary structures. The aim of this minireview was to describe the safety, efficacy, and clinical indications of these techniques in the treatment of patients with intrahepatic cholangiocarcinoma who are ineligible for surgery.

Keywords: Interventional ultrasonography; Intrahepatic cholangiocarcinoma; Irreversible electroporation; Microwaves ablation; Percutaneous ablation; Radiofrequency ablation; Thermal ablation.

Figure 1

Microwave ablation. A: Intrahepatic cholangiocarcinoma (arrows) in the sixth segment of the liver; B: The antenna (subtle arrow) is inserted into the tumor, and the generator is on. See the time in the top right. The hyperechoic appearance (arrows) corresponds to the steam generated by heat and reflects the ablated area from microwave application; C: After 1 minute, almost all nodules become hyperechoic except for a small, round, hypoechoic area (arrows) in the top left; D: The entire nodule is hyperechoic (arrows) after 2 minutes from the start of microwave application, indicating complete necrosis of the nodule. T: Intrahepatic cholangiocarcinoma nodule.

Figure 2

Irreversible electroporation. A: A 3 cm intrahepatic cholangiocarcinoma hypoechoic nodule (arrows) is located between the inferior vena cava and the main portal trunk as shown by power Doppler ultrasound (US); B: US appearance of two probes (arrows) inserted into the tumor; C: Contrast-enhanced US shows complete necrosis of the tumor. IVC: Inferior vena cava; PV: Portal vein; T: Intrahepatic cholangiocarcinoma nodule.