Transarterial radioembolization for hepatocellular carcinoma: An update and perspectives

Abstract

In the last decade trans-arterial radioembolization has given promising results in the treatment of patients with intermediate or advanced stage hepatocellular carcinoma (HCC), both in terms of disease control and tolerability profile. This technique consists of the selective intra-arterial administration of microspheres loaded with a radioactive compound (usually Yttrium90), and exerts its therapeutic effect through the radiation carried by these microspheres. A careful and meticulous selection of patients is crucial before performing the radioembolization to correctly perform the procedure and reduce the incidence of complications. Radioembolization is a technically complex and expensive technique, which has only recently entered clinical practice and is supported by scant results from phase III clinical trials. Nevertheless, it may represent a valid alternative to transarterial chemoembolization (TACE) in the treatment of intermediate-stage HCC patients, as shown by a comparative retrospective assessment that reported a longer time to progression, but not of overall survival, and a more favorable safety profile for radioembolization. In addition, this treatment has reported a higher percentage of tumor shrinkage, if compared to TACE, for pre-transplant downsizing and it represents a promising therapeutic option in patients with large extent of disease and insufficient residual liver volume who are not immediately eligible for surgery. Radioembolization might also be a suitable companion to sorafenib in advanced HCC or it can be used as a potential alternative to this treatment in patients who are not responding or do not tolerate sorafenib

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“…Embolization of the any extrahepatic branch is conducted to avoid dispersion of microspheres to duodenum, stomach, or other nontargeted organs, and then macroaggregates of albumin labeled with technetium Tc 99 are injected. The diffusion of these particles is studied by a single photon emission computed tomography 18 (Figure 4). A single-center prospective cohort study of 291 patients treated with TARE found a complete response rate of 23% and a partial response rate of 34%.…”

Comparison of Adverse Events Between Selective Internal Radiation Therapy Versus Sorafenib in Locally Advanced Hepatocellular Carcinoma in Mongolia: A Subgroup Analysis of SIRveNIB Study

“…Selective Internal Radiation Therapy (SIRT) is a form of radiotherapy that utilizes selective trans-arterial administration of radioactive yttrium90 microspheres [13]. In SIRT, radiation is the main therapeutic mechanism rather than embolization in causing of death of tumor cells [13].…”

“…In SIRT, radiation is the main therapeutic mechanism rather than embolization in causing of death of tumor cells [13]. The first comprehensive European experience using SIR-Spheres ® for the treatment of patients with inoperable HCC reported an overallbest response rate of stable disease or partial response in 88% of patients byRECIST criteria and median overall survival was 7 months (95% CI, 2 -12 months) [14].…”

Consensus for Radiotherapy in Hepatocellular Carcinoma from The 5th Asia-Pacific Primary Liver Cancer Expert Meeting (APPLE 2014): Current Practice and Future Clinical Trials

“…SIRT, also known as TARE, or simply as radioembolization, is a form of RT delivery that utilizes selective transarterial administration of microspheres loaded with radioisotopes, like yttrium 90, iodine 121, or rhenium [62]. The short tissue penetration distance (average 2.5 mm, maximal 11 mm in Yttrium 90) which is mainly used in SIRT is ideal for brachytherapy and it avoids concomitant radiation damage to surrounding liver parenchyma.…”