Pressure Gradient-Driven Embolization b-TACE for HCC: Technical and Diagnostic Step-by-Step Procedural Guide and Literature Review

Abstract

Background: Hepatocellular carcinoma (HCC) is one of the leading cause of cancer death worldwide. Transarterial therapies represent an important tool in the management of different clinical scenarios, from a patient with a single nodule to a patient with multinodular disease. Up to 30% of patients are diagnosed with intermediate-stage HCC, and transarterial chemoembolization (TACE) represents the mainstay of treatment. Overall survival in patients with HCC undergoing TACE is strongly influenced by obtaining a sustained complete response, which is strongly affected by the HCC's dimension. Methods: Pressure gradient-driven embolization, achieved by employing a microballoon catheter in the balloon-occluded TACE (bTACE), represents the most novel innovation in the field of transarterial therapies in the last decade. In fact, bTACE, thanks to its ability to redistribute flow towards tumor territories, can allow higher chemotherapeutic drug concentrations, leading to better oncological performance, especially in patients in which standard TACE struggles to obtain a complete response. Conclusions: This technical and diagnostic intraprocedural step-by-step guide, discussed with a review of the existing literature, will enable readers to achieve an optimal procedure and to convey to their patients the full clinical benefits of these procedures.

Keywords: hepatocellular carcinoma; microballoon interventions; transarterial chemoembolization.

Figure 1

Clinical case of an 82-year-old female with HCC in HCV-related cirrhosis, treated with multiple locoregional treatments until 2022. In April 2024, an HCC nodule (sVII) up to 5 cm was newly diagnosed. The selective DSA performed with the deflated microballoon catheter (A) depicted the slightly hypervascular HCC, but not its microvasculature. The microballoon catheter’s inflation (dotted circle) due to flow redistribution improved HCC vascularization and the detection of its microvascularization, with a better subsequent diagnostic value of the DSA (B).

Figure 2

Clinical case of DEM-bTACE in a 41-year-old man with HBV-related cirrhosis, performed as bridging to orthotopic liver transplant. Pre-procedural arterial phase CT (A) showed a single 5.5 cm hepatocellular carcinoma in segment II-III. The transfemoral digital subtraction angiography of the common hepatic artery (right oblique 25°) (B) and the Dual-Phase Cone Beam CT ((C), delayed phase) confirmed the HCC nodule and vascular anatomy. VR reconstruction obtained from the arterial phase Cone Beam CT dataset (D) depicts the correct segment of the artery for microballoon positioning. After balloon inflation (dotted circle), embolization (E) was performed with 100 and 200 μm microspheres loaded with 100 mg of epirubicin. CT performed at 1 month ((F), arterial phase) showed a complete response. The patient underwent an orthotopic liver transplant 7 months after bTACE.