Usefulness of virtual parenchymal perfusion software visualizing embolized areas to determine optimal catheter position in superselective conventional transarterial chemoembolization for hepatocellular carcinoma

Perspectives of Cone-beam Computed Tomography in Interventional Radiology: Techniques for Planning, Guidance, and Monitoring

Cone-beam computed tomography (CBCT) has emerged as a prominent imaging modality in interventional radiology that offers real-time visualization and precise guidance in various procedures. This article aims to provide an overview of the techniques used to guide and monitor interventions that use CBCT. It discusses the advantages of CBCT, its current applications, and potential future CBCT-related developments in the field of interventional radiology.

Initiative on Superselective Conventional Transarterial Chemoembolization Results (INSPIRE)

Several publications show that superselective conventional TransArterial ChemoEmbolization (cTACE), meaning cTACE performed selectively with a microcatheter positioned as close as possible to the tumor, improves outcomes, maximizing the anti-tumoral effect and minimizing the collateral damages of the surrounding liver parenchyma. Recent recommendations coming from the European Association for the Study of the Liver (EASL) and European Society of Medical Oncology (ESMO) highlighted that TACE must be used in Hepatocellular Carcinoma (HCC) "selectively targetable" and "accessible to supraselective catheterization." The goal of the manuscript is to better define such population and to standardize superselective cTACE (ss-cTACE) technique. An expert panel with extensive clinical-procedural experience in TACE, have come together in a virtual meeting to generate recommendations and express their consensus. Experts recommend that anytime cTACE is proposed, it should be ss-cTACE, preferably with a 1.5-2.0 Fr microcatheter. Ideally, ss-cTACE should be proposed to patients with less than five lesions and a maximum number of two segments involved, with largest tumor smaller than 5 cm. Angio Cone-Beam Computed Tomography (CBCT) should be used to detect enhancing tumors, tumor feeders and guide tumor targeting. Whole tumor volume should be covered to obtain the best response. Adding peritumoral margins is encouraged but not mandatory. The treatment should involve a water-in-oil emulsion, whose quality is assessable with the "drop test." Additional particulate embolization should be systematically performed, as per definition of cTACE procedure. Non-contrast CBCT or Multi-Detector Computed Tomography (MDCT) combined with angiography has been considered the gold standard for imaging during TACE, and should be used to assess tumor coverage during the procedure. Experts convene that superselectivity decreases incidence of adverse effects and improves tolerance. Experts recommend contrast-enhanced Computed Tomography (CT) as initial imaging on first follow-up after ss-cTACE, and Magnetic Resonance Imaging (MRI) if remaining tumor viability cannot be confidently assessed on CT. If no response is obtained after two ss-cTACE sessions within six months, patient must be considered unsuitable for TACE and proposed for alternative therapy. Patients are best served by multidisciplinary decision-making, and Interventional Radiologists should take an active role in patient selection, treatment allocation, and post-procedural care.

Efficacy of Superselective Conventional Transarterial Chemoembolization Using Guidance Software for Hepatocellular Carcinoma within Three Lesions Smaller Than 3 cm

Simple Summary

Although transarterial chemoebolization (TACE) is indicated for small hepatocellular carcinoma (HCC) as a second choice, TACE for small HCC is frequently difficult and less effective because of less hypervascularity and the presence of tumor portions receiving a dual blood supply. The aim of this study was to evaluate the efficacy of superselective cTACE under guidance software for patients with HCC within three lesions smaller than 3 cm. By using TACE guidance software, 81.2% of HCC lesions could be completely embolized and the cumulative local tumor progression rates in 303 tumors at 1, 3, 5, and 7 years were 17.8, 27.8, 32.0, and 36.0%, respectively. The 1-, 3-, 5-, and 7-year overall and recurrence-free survival rates in 175 patients were 97.1 and 68.7, 82.8 and 34.9, 64.8 and 20.2, and 45.3 and 17.3%, respectively. Our results indicate the efficacy of superselective cTACE using guidance software for HCC within three lesions smaller than 3 cm.

Abstract

The indication of transarterial chemoembolization (TACE) has advanced to hepatocellular carcinoma (HCC) of Barcelona Clinic Liver Cancer (BCLC) stage A when surgical resection (SR), thermal ablation, and bridging to transplantation are contraindicated; however, TACE for small HCC is frequently difficult and ineffective because of less hypervascularity and the presence of tumor portions receiving a dual blood supply. Here, we report outcomes of superselective conventional TACE (cTACE) for 259 patients with HCCs within three lesions smaller than 3 cm using guidance software. Automated tumor feeder detection (AFD) functionality was applied to identify tumor feeders on cone-beam computed tomography during hepatic arteriography (CBCTHA) data. When it failed, the feeder was identified by manual feeder detection functionality and/or selective angiography and CBCTHA. Regarding the technical success in 382 tumors (mean diameter, 17.2 ± 5.9 mm), 310 (81.2%) were completely embolized with a safety margin (5 mm wide for HCC ≤25 mm and 10 mm wide for HCC >25 mm). In 61 (16.0%), the entire tumor was embolized but the safety margin was not uniformly obtained. The entire tumor was not embolized in 11 (2.9%). Regarding the tumor response at 2–3 months after cTACE in 303 tumors excluding those treated with combined radiofrequency ablation (RFA) or SR and lost to follow-up, 287 (94.7%) were classified into complete response, seven (2.3%) into partial response, and nine (3.0%) into stable disease. The mean follow-up period was 44.9 ± 27.6 months (range, 1–109) and the cumulative local tumor progression rates at 1, 3, 5, and 7 years were 17.8, 27.8, 32.0, and 36.0%, respectively. The 1-, 3-, 5-, and 7-year overall and recurrence-free survival rates in 175 patients, excluding those with Child–Pugh C class, who died of other malignancies, or who underwent combined RFA or hepatic resection, were 97.1 and 68.7, 82.8 and 34.9, 64.8 and 20.2, and 45.3 and 17.3%, respectively. Our results indicate the efficacy of superselective cTACE using guidance software for HCC within three lesions smaller than 3 cm.