Safety and Feasibility of Stereotactic Body Radiation Therapy for Patients With Hepatocellular Carcinoma and Advanced Cirrhosis Awaiting Liver Transplantation: A Prospective Pilot Clinical Trial.

[PURPOSE] Liver transplantation is the definitive treatment for hepatocellular carcinoma (HCC) in eligible patients with cirrhosis. Bridging liver-directed therapies are critical for maintaining transplant eligibility during long wait times. However, due to the fear of decompensation, many advanced cirrhotic patients are excluded from receiving liver-directed therapies. This prospective pilot clinical trial evaluated the feasibility, safety, and efficacy of stereotactic body radiation therapy (SBRT) as a bridging therapy in an advanced cirrhotic HCC population.

[METHODS AND MATERIALS] HCC patients with Child-Pugh B8 or worse cirrhosis and eligible for liver transplant were enrolled. SBRT to 40 Gy in 5 fractions was delivered to a single HCC as a bridging strategy. The primary endpoint was the proportion of patients who were transplant eligible up to 1 year following SBRT. Secondary endpoints included disease control per modified Response Evaluation Criteria in Solid Tumors, proportion of patients that proceeded to transplant, incidence of nonclassical radiation-induced liver disease (RILD) within 1 week to 3 months after SBRT, and incidence of liver toxicity per Common Terminology Criteria for Adverse Events v5.0.

[RESULTS] Between 2019 and 2023, 9 patients with Child-Pugh B8 or worse cirrhosis were enrolled. Median follow-up was 11.2 months with a 22% death rate. Six patients (67%) were transplanted or remained transplant eligible 1 year after SBRT. Three patients (33%) failed to receive a liver transplantation: 2 due to factors unrelated to SBRT or tumor progression, and 1 patient experienced minimal tumor progression outside of Milan criteria. Per modified Response Evaluation Criteria in Solid Tumors, the local control rate was 100% and the incidence of intrahepatic and extrahepatic disease progression was 0%. Within 1 week to 3 months after SBRT, 1 patient (11%) experienced liver toxicity (Common Terminology Criteria for Adverse Events grade 4 acidosis, acute hepatic encephalopathy, and hepatic failure), but there were no instances of nonclassical RILD.

[CONCLUSIONS] Bridging SBRT in patients with HCC and advanced cirrhosis may safely maintain transplant eligibility without increasing the risk of nonclassical RILD.