PO-0704: Proton beam therapy for hepatocellular carcinoma with extensive portal vein tumor thrombosis. (April 2015) - Okumura, T.; Fukumitsu, N.; Mizumoto, M.; Ishikawa, H.; Ohnishi, K.; Murofushi, K.; Numajiri, H.; Fukuda, K.; Abei, M.; Aihara, T.; Sakae, T.; Tsuboi, K.