Dose-escalated external beam radiotherapy in unresectable hepatocellular carcinoma.

Abstract

267 Background: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Data regarding the use of external beam radiotherapy is limited in patients from populations without endemic viral hepatitis. We examine the outcomes for patients treated with external beam radiotherapy in the modern era at a single institution. Methods: A total of 29 patients with localized HCC treated from 2000 to 2009 were reviewed. Patients with metastatic disease at the time of radiation were excluded. Median radiation dose was 50 Gy (range 30-75 Gy) with a median biologically effective dose (BED) of 80.6 (range 60-138.6). Median tumor size at the time of radiation was 5.2 cm (range 2-25 cm). Results: Median residual tumor following radiation was 80% (range 27%-278%), with a median residual α-fetoprotein of 47% (range 0.8%-8240%). Estimated one-year overall survival (OS) and in-field progression-free survival (PFS) rates for the study population were 56% and 79%, respectively. One year OS in patients treated to a BED <75 was 18% vs. 69% in patients treated to a BED ≥75 (p=0.002). One year in-field PFS rate (60% vs. 88%, p=0.023) and biochemical PFS duration (median 6.5 vs. 1.6 mos., p=0.001) were also significantly improved in patients treated to a BED ≥75. Grade 3 toxicity was seen in only 13.8% of patients. Conclusions: In a population without endemic viral hepatitis, unresectable HCC demonstrates significant response toexternal beam radiotherapy with minimal toxicity. Furthermore, our findings suggest that increased BED is associated with improved survival and local tumor control. No significant financial relationships to disclose.