Source Liver Unit, Clinica Universidad de Navarra, Pamplona, Spain; Centro de Investigacion Biomedica en Red de Enfermedades Hepaticas y Digestivas (CIBEREHD), Pamplona, Spain.
Radioembolization is a form of brachytherapy in which intraarterially injected (90)Y-loaded microspheres serve as sources for internal radiation purposes. It produces average disease control rates above 80% and is usually very well tolerated. Main complications do not result from the microembolic effect, even in patients with portal vein occlusion, but rather from an excessive irradiation of non-target tissues including the liver.
All the evidence that support the use of radioembolization in HCC is based on retrospective series or non-controlled prospective studies. However, reliable data can be obtained from the literature, particularly since the recent publication of large series accounting for nearly 700 hundred patients. When compared to the standard of care for the intermediate and advance stages (transarterial embolization and sorafenib), radioembolization consistently provides similar survival rates. Two indications seem particularly appealing in the boundaries of these stages for first-line radioembolization.
First, the treatment of patients straddling between the intermediate and advanced stages (intermediate patients with bulky or bilobar disease that are considered poor candidates for TACE, and advanced patients with solitary tumors invading a segmental or lobar branch of the portal vein). Second, the treatment of patients that are slightly above the criteria for resection, ablation or transplantation, for which downstaging could open the door for a radical approach. Radioembolization can also be used to treat patients progressing to TACE or sorafenib. With a number of clinical trials underway, the available evidence shows that it adds a significant value to the therapeutic weaponry against HCC of tertiary care centers dealing with this major cancer problem.