The use of stereotactic body radiotherapy as a bridge to liver transplantation for hepatocellular carcinoma.

Abstract

418 Background: Approximately 30% of patients with hepatocellular carcinoma (HCC) on the wait list for liver transplant (LT) fall off the transplant list due to progressive HCC. Stereotactic Body Radiotherapy (SBRT) has been used as a “bridge” to LT in patients who are not amenable to RFA or TACE. Methods: Baseline patient characteristics, radiotherapy details and outcomes were reviewed in HCC patients who received SBRT as a bridge to LT. Results: Between July 2004 and Dec. 2014, 601 patients with HCC were listed for LT, of which 400 (66.5%) received bridging therapy. 38 patients, at high risk for HCC progression, were unsuitable for RFA or TACE, receiving SBRT as a bridging therapy. Median SBRT dose was 36Gy in 6 fractions (range 8.5-48Gy in 1 – 6 fractions), including 1 patient who was transplanted after receiving one fraction. 25 of 38 patients (67%) had all lesions treated (median number of lesions 2 {1-8}); 13 patients received SBRT only to the dominant lesion at highest risk of growing or rupturing. At the time of SBRT, 42% had HCC within Milan criteria, and median Child Pugh score was A6 (range A5-B8). 5 patients (13%) dropped off the transplant wait list due to development of metastatic disease (4) and macrovascular invasion with progressive disease (1). Median irradiated HCC volume was 60.5cc (range 7-216cc). Median liver volume (minus HCC) was 1491cc (737-2728cc). Median mean dose to the liver minus HCC was 11.2Gy (2.8-18.6Gy) and median effective liver volume irradiated was 28% (11-66%). 1 patient was admitted 2 months post SBRT with hepatic pain - possibly attributable to SBRT and another patient developed a rib fracture 8 months post SBRT (max rib dose 43Gy in 6 fractions). No other specific SBRT toxicity was noted. The 1-, 3- and 5-year disease free survival and actuarial survival of HCC patients treated with SBRT who went on to have transplant was 93%, 79% and 79%, and 89%, 76% and 76% respectively. Including patients who dropped off the transplant list, the intent-to-treat 1-, 3 - and 5-year survival was 89%, 65% and 65%. There was no reported increase in operative morbidity at the time of transplant in patients treated with SBRT. Conclusions: SBRT can be used safely and effectively in HCC patients as a bridge to liver transplant.