Proton beam therapy for hepatocellular carcinoma with portal vein tumor thrombus.

Background: Treatment modalities for patients with hepatocellular carcinoma (HCC) who have portal vein tumor thrombus (PVTT) are limited and controversial; furthermore, the prognosis for these patients is extremely poor. The authors conducted a retrospective review to determine the role of proton beam therapy in the treatment of patients who had HCC with PVTT.
Methods: Twelve patients with HCC who had tumor thrombus in the main trunk or major branches of the portal vein (clinical T3-T4N0M0) were treated with proton beam therapy. At the time they received proton beam irradiation, patients ranged in age from 42 years to 80 years (median, 62 years), and their tumors ranged in size from 40 mm to 110 mm (median, 60 mm) in greatest dimension. A total dose of 50-72 gray (Gy) (median, 55 Gy) in 10-22 fractions was delivered to the tumors, including PVTT.
Results: All tumors that were treated with proton beam therapy remained controlled at a median follow-up of 2.3 years (range, 0.3-7.3 years). Among 12 patients, 10 patients had new liver tumors outside the irradiated volume 0.1-2.4 years after proton beam therapy, and 3 patients also had distant metastases; consequently, 8 patients died of disease, and 2 patients were salvaged by further therapies. The remaining two patients were alive with no evidence of disease 4.3 years and 6.4 years after proton beam therapy. The progression-free survival rates were 67% at 2 years and 24% at 5 years. The median progression-free survival was 2.3 years. According to the Acute Radiation Morbidity Scoring Criteria (Radiation Therapy Oncology Group), therapy-related toxicity > or = Grade 3 was not observed.
Conclusions: Proton beam therapy for patients with HCC who had PVTT was feasible and effective. It appeared to improve survival and local control significantly for these patients.