Transarterial chemoembolization versus transarterial radioembolization in hepatocellular carcinoma: optimization of selecting treatment modality

Hepatocellular carcinoma (HCC) of intermediate stage consists of diverse tumor and patient factors in terms of tumor number, size and liver function resulting in various outcomes given by transarterial chemoembolization (TACE). Transarterial radioembolization (TARE) using radioactive isotope, beta-ray emitting Yttrium-90 with a short half-life and penetration depth, is an emerging intra-arterial brachytherapy characterized by potent anti-cancer effect given by radiation but minimal embolic effect. Although there is lack of study directly comparing the efficacy and safety between TACE and TARE in patients with unresectable HCC, several retrospective or small-scaled studies suggest that overall efficacy indicated by overall survival and time to progression is similar between two modalities and TARE has a superiority in the safety including postembolization syndrome, hospitalization days and outpatient-based therapy. In advanced HCC with portal vein (PV) invasion, TACE is not consistently recommended due to risk of hepatic decompensation or failure after procedure. On the contrary, available data suggest that TARE might be a promising treatment option in HCC with PV thrombosis if patient's liver function is preserved and the level of PV invasion is less than main trunk. Ongoing trials comparing TARE and sorafenib in advanced HCC would elucidate the role of this locoregional therapy. The need of a multidisciplinary team, complex steps of procedure and high cost of TARE are the hurdles to widespread recommendation of this therapy in intermediate or advanced HCC. The optimization of selection between TACE and TARE might be dependent on availability, experience, tumor factors and patient factors.