Radioembolization for hepatocellular carcinoma

Abstract

Radioembolization is a form of brachytherapy in which intra-arterially 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 patients. When compared to the standard of care for the intermediate and advanced 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.

Semi-Quantitative Analysis of Post-Transarterial Radioembolization 90Y Microsphere Positron Emission Tomography Combined with Computed Tomography (PET/CT) Images in Advanced Liver Malignancy: Comparison With 99mTc Macroaggregated Albumin (MAA) Single Photon Emission Computed Tomography (SPECT)

“…Moreover, 99m Tc MAA images are not considered to be ideal method to predict the actual distribution of the 90 Y microspheres. Recent reports have postulated that there is a discordance between 99m Tc MAA and 90 Y microsphere bremsstrahlung SPECT [12,28,29].…”

Transarterial Radioembolization: A New Selection to Treat Hepatocellular Carcinoma

“…But the effective rates became 80% with the EASL criteria (Bruno et al 2012, Lewandowski et al 2009. Recent studies show that the mRECIST criteria could be more objective.…”

“…The side effect of radiation embolism is relatively weak, manifested as fatigue, mild abdominal pain or discomfort, with or without cachexia, elevated bilirubin and similar flu-like symptoms, some experts call it post-radioembolization syndrome (Bruno S, et al, 2012). The incidence of PRS reported by literature is 12% to54% (Hyun Young Woo and Jeong Heo, 2015), and self-relieved within ten hours.…”

A review of 3D image-based dosimetry, technical considerations and emerging perspectives in 90Y microsphere therapy

“…Although it has been postulated that the optimal combination of specific activity and embolic load is somewhere between that of GMS and RMS [37], recent work shows that the overall survival of patients treated with either GMS or RMS across different HCC stages is quite consistent [38]. A multicentre study of hepatic metastatic neuroendocrine tumours showed a statistically significant greater median absorbed dose to liver lobes delivered using GMS (right 117 Gy, left 108 Gy), than using RMS (right 50.8 Gy, left 44.5 Gy), although a similar disease control rate for both (92% GMS and 94% RMS were partial responders or stable disease) after 6 months [39].…”