Long-term outcome analysis of Y90 radioembolization in hepatocellular carcinoma

Background: Yttrium-90 (Y90) radioembolization is a catheter-based therapy for hepatocellular carcinoma (HCC). Multiple trials have evaluated the efficacy of Y90 in HCC; however, few have assessed long-term hepatic function. This study aimed to evaluate a clinical real-world experience of Y90 effectiveness and long-term impact on hepatic function. Methods: A single-center retrospective chart review was performed for patients with Child-Pugh (CP) class A or B who received Y90 for primary HCC between 2008 and 2016. Model for end-stage liver disease (MELD) and CP scores were calculated on the day of treatment and 1, 3, 6, 12, and 24 months post-procedure. Results: Of the 134 patients included, the mean age was 60 years old and median overall survival (OS) from date of diagnosis was 28 months [95% confidence interval (CI): 22.21-38.05]. Patients with CP class A (85%) had a median progression-free survival (PFS) of 3 months (95% CI: 2.99-5.55) and median OS of 17 months (95% CI: 9.59-23.10) from date of Y90 treatment compared to a median PFS of 4 months (95% CI: 2.07-8.28) and OS of 8 months (95% CI: 4.60-15.64) for patients with CP class B. MELD scores were significantly higher post-treatment than pre-treatment, with significant recovery at 24 months. No significant differences were seen between cancer stage and OS, while PFS and cancer stage did show difference between cancer stage 1 and 3 with longer median PFS seen in stage 1. Conclusions: While our study supports the literature for OS in Y90-treated patients, we found a shorter PFS in this population. This may reflect the differences between the utilization of RECIST in clinical trials and clinical radiology practice in determining progression. Significant factors associated with OS were age, MELD, CP scores and portal vein thrombosis (PVT). For PFS, CP score and stage at diagnosis were significant. Increasing MELD scores over time likely reflected a combination of radioembolization-induced liver disease, liver decompensation or progression of HCC. The downtrend at 24 months is likely due to long term survivors with significant benefit from therapy with no long-term complications from Y90.