2021 - The Impact of Viral Etiology on External Beam Radiation Treatment for Hepatocellular Carcinoma Associated Portal Vein Tumor Thrombosis

03:00pm - 04:00pm ET

Poster Hall - Exhibit Hall A

Screen: 28

POSTER

Presenter(s)

Donovan Brown, BS - UVA Department of Radiation Oncology, Charlottesville, VA

D. Brown¹, H. Batchelor², E. Asare³, and E. Janowski⁴; ¹School of Medicine, University of Virginia, Charlottesville, VA, ²Department of Anesthesiology, University of Maryland, Baltimore, MD, ³Department of Radiation Oncology, UMass Chan Medical School, Worcester, MA, ⁴Department of Radiation Oncology, University of Virginia, Charlottesville, VA

Purpose/Objective(s): Hepatocellular carcinoma (HCC) is derived from a background of chronic inflammation from both viral and environmental factors. HCC-associated portal vein tumor thrombosis (PVTT) is a poor prognostic marker, often limiting survival to several months. While external beam radiation therapy (EBRT) plays a crucial role in the management of HCC PVTT, the optimal radiation dose and fractionation remain areas of active investigation. We hypothesized that dose-escalated EBRT for HCC PVTT improves outcomes without increasing toxicity and that this benefit may be influenced by viral etiology.

Materials/Methods: We conducted a retrospective review of patients with HCC PVTT treated at our institution with EBRT from 2005-2025, examining baseline characteristics, treatment modalities, and clinical outcomes. Patients receiving BED10 < 58 Gy were analyzed in the low-dose cohort, while those receiving = 58 Gy comprised the high-dose cohort. Adverse events were recorded and graded using CTCAE v5.0 criteria. Survival analyses were performed using Kaplan-Meier methodology with log-rank testing in R.

Results: Forty-nine patients were included: 12 in the low-dose group and 37 in the high-dose group. Groups had similar median age (65 vs. 63 years), female sex (33% vs. 24%), and baseline ECOG performance status (p = 0.13). Rates of hepatitis viral origin (42% vs. 57%) and viral treatment among viral patients (40% vs. 62%; p = 0.62) were comparable. AJCC stage distribution (p = 0.18), median initial tumor diameter (5.4 cm vs. 6.5 cm), degree of portal vein occlusion (64% vs. 40%; p = 0.19), and Child-Pugh score distribution (p = 0.62) were similar. Log-transformed initial alpha-fetoprotein levels were lower in the high-dose group (2.0 vs. 2.9; p = 0.04). High-dose EBRT was associated with lower rates of post-treatment therapeutic paracentesis requirement (30% vs. 67%; p = 0.02), though rates of PVTT resolution were similar (p = 0.99). Highest acute (p = 0.82) and late (p = 0.93) toxicity distributions were comparable. There were no grade 4 or 5 toxicities. The high-dose group demonstrated improved median overall survival (4.2 vs. 8.5 months; p = 0.01). Among patients with hepatitis virus-associated HCC, high-dose EBRT improved overall survival (1.8 vs. 9.1 months; p < 0.001), whereas dose did not impact survival in the non-viral HCC group (5.5 vs. 7.0 months; p = 0.35).

Conclusion: Dose-escalated EBRT for HCC with PVTT is associated with improved overall survival without increased toxicity, and this survival benefit appears driven by patients with hepatitis virus-associated disease.