Radiation Major Hepatectomy Using Ablative Dose Yttrium-90 Radioembolization in Patients with Large Hepatocellular Carcinoma ≥ 5 cm

To evaluate the safety and effectiveness of ablative radioembolization for large hepatocellular carcinoma (HCC) while preserving a small future liver remnant (FLR).Twenty-five patients with large HCC ≥ 5 cm, requiring treatment for > 60% of the total liver volume and having well-preserved liver function, were treated with ablative radioembolization at a single institute from January 2017 to December 2021. Radioembolization was performed with a mean absorbed dose of > 150 Gy, and the FLR per non-tumor liver volume (NTLV) was set at > 30%. Changes in liver function, adverse events, duration of response (DoR) in a treated area, time-to-progression (TTP), and overall survival (OS) were retrospectively investigated.The largest tumor diameter and planned dose per treated volume were 11.4 ± 3.9 cm and 242.3 ± 63.6 Gy (169.4 ± 45.9 Gy per whole liver volume), respectively. All patients remained at Child-Pugh class A for 90 days. No patients experienced grade 3‒4 hyperbilirubinemia or new ascites. One patient (lung dose, 27.8 Gy) developed radiation pneumonitis requiring transient steroid treatment. According to the post-treatment dosimetry, the tumor and non-tumorous liver absorbed dose were 418.8 ± 227.4 and 69.0 ± 32.1 Gy, respectively. The median DoR in a treated area and TTP were 22.0 and 17.1 months, respectively. The 5-year OS rate was 83.2%.Ablative radioembolization of large HCC ≥ 5 cm can be safely and effectively performed in patients with preserved liver function when FLR / NTLV exceeds 30%.