Stereotactic Body Radiation Therapy: A New Strategy for Loco-Regional Treatment for Hepatocellular Carcinoma While Awaiting Liver Transplantation.

ABSTRACT

BACKGROUND: Trans-arterial chemoembolization and radiofrequency ablation are commonly used for control of hepatocellular carcinoma (HCC) on liver transplant (LTx) waiting list. Stereotactic body radiation therapy (SBRT) was introduced to our institution for HCC as a bridging or downsizing therapy to LTx. PATIENTS AND METHODS: Twenty-five HCC lesions in 22 patients were treated with SBRT while waiting for LTx from January 2010 to December 2015. Nineteen of these patients received deceased donor LTx. SBRT was defined as 40-50 Gy delivered in 4-6 fractions. Pre- and post-liver transplant outcome were analyzed in addition to the dropout rate and tumor response to SBRT. RESULTS: Median size of original tumors was 3.2 cm (2.0-8.9), and median size of tumor after SBRT was significantly smaller at 0.9 cm (0-3.2) in the explanted livers (p < 0.01). The dropout rate was 9%, and they were only downsized patients outside of Milan criteria. Liver disease did not progress between pre- and post-SBRT except one patient. Twenty-eight percent of treated HCCs showed complete pathologic response, and 22% had extensive partial response with some residual tumor. No HCC recurrence was experienced after LTx. CONCLUSION: SBRT is indicated to be safe, effective treatment for HCC on LTx waiting list, and it leads to satisfactory post-liver transplant outcomes.