CIO 2021-13 Long-term Clinical Outcomes of Yttrium-90 Transarterial Radioembolization for Hepatocellular Carcinoma

Purpose: The aim of this study is to examine the clinical outcomes of yttrium-90 (Y90) transarterial radioembolization (TARE) of primary hepatocellular carcinoma (HCC) through evaluation of a 5-year institutional experience.

Material and Methods: This retrospective study evaluated 88 consecutive patients with primary HCC receiving Y90 TARE treatments at an academic medical center from 2015 to 2020. Clinical outcomes were elucidated by examination of complications, liver function tests (LFTs), biochemical response (alpha-fetoprotein - AFP), and radiographic response at least 1-month post-treatment. Radiographic response was assessed 1-month, 3-months, and 6-months after treatment to determine objective response ratio (ORR) and disease control rate (DCR). The average size of the liver lesion was 5.0cm ± 3.38 (range: 1.0-18.6cm). Hepatic disease distribution was bilobar for 60.2% of patients and 37.5% of patients had a model for end-stage liver disease (MELD) score of at least 10. Prior invasive treatment was attempted in 56.8% of patients, none of which were liver transplants. The average Y90 treatment dose was 127.8 Gy ± 20.2.

Results: Of the 73.9% of patients with AFP-producing tumors, 67.7% had a complete or partial biochemical response 1-month post-treatment. On cross-sectional imaging, by 6-months following treatment, the ORR was 83.3% (complete or partial response) and DCR was 98.3% (complete response, partial response, or stable disease). Furthermore, 96.7% of patients had a response that lasted longer than 6 months after treatment. Functional outcomes were maintained or improved in 79.6% of patients 6-months post-treatment and 76.1% of patients 1-year post-treatment. The average survival was 14.0 months ± 13.0, with 9.1% of patients surviving past 3 years. At 6-months post-treatment, 77.3% of patients gained or maintained Milan criteria, which was maintained for 74.4% and 70.0% of patients 1-year and 2-years after treatment, respectively. There were 5.7% of patients that ultimately went on to receive liver transplants.

Conclusions: Y90 TARE is an effective treatment option for primary HCC with an ORR greater than 80% and DCR greater than 95%. Enduring outcomes of this therapy further act as a realistic bridge to liver transplantation, with 70% of patients maintaining Milan criteria 2-years after treatment.