Feasibility of Boosted Radioembolization for Hepatocellular Carcinoma Larger than 5 cm

To address the feasibility of yttrium-90 (⁹⁰Y) glass microspheres administered at a boosted dose in large hepatocellular carcinomas (HCCs).

From July 2016 to August 2017, 20 patients who underwent ⁹⁰Y radioembolization for treatment-naïve HCC met the following inclusion criteria: (i) nodular tumor, (ii) tumor size > 5 cm, (iii) Barcelona Clinic Liver Cancer stage A/B disease, (iv) target perfused tissue dose > 150 Gy, and (v) all tumors treated in 1 session of radioembolization. Follow-up radiologic findings and clinical outcomes were retrospectively reviewed until May 2018. Tumor response was determined per modified Response Evaluation Criteria In Solid Tumors.

Mean total radiation activity infused was 4.96 GBq ± 1.82 (median, 4.88 GBq; range, 1.63-9.15 GBq). Mean target perfused tissue dose was 263.5 Gy ± 95.2 (median, 241.6 Gy; range, 156.2-550.6 Gy). The mean number of vials used per treatment was 4.15 ± 1.4 (median, 4; range, 2-7). Complete response rates were 25% at 1 month and 60% at 3 months. Complete response of the primary index tumor was achieved in 16 patients (80%) based on best tumor response. Local progression-free survival and progression-free survival rates were 94.1% and 85.0% at 6 mo and 94.1% and 74.7% at 1 year, respectively. Four patients (20%) had symptomatic (n = 3) or asymptomatic (n = 1) benign biliary strictures.

Radioembolization with a boosted dose in patients with large HCCs may show favorable tumor response, but with considerable biliary complications.