Phase II Trial of Palliative Radiation Therapy for Symptomatic Hepatocellular Carcinoma and Liver Metastases

superior to those in Group A (48.5%, 32.4%), but no significant difference was observed. The 1and 2-year OSs were 75.9% and 36.9% in Group A, 75.0% and 58.3% in Group B, and 81.0% and 52.3% in Group C. These 2year survival rates were superior to previously reported data after conventional irradiation with TMZ in EORTC-NCIC trial. Five-year OS of patients in Group B (29.2%) was superior to that in Group C (2.8%). As for the adverse events, there was no significant difference in RNFSs. The 1and 2-year SNFSs in Group B (92.3%, 61.5%) were better than those in Group A (82.5%, 41.3%) and in Group C (67.1%, 23.5%). Group B showed 2.7-fold lower risk for necrosis in SVZ in compared with Group C, although the statistical significance was not proven (p Z 0.122). Conclusions: In MGMT-Met cases, reduction of treatment dose demonstrated the same effect on local control, but the same risk for in-field necrosis. This reduced-dose IMRT (48 Gy/8Fx.) showed tendency to decrease the risk for necrosis in SVZ and it might result in increased rates of long survivor. However, the effective dose delivery to target while avoiding the dose for SVZ was still difficult even with IMRT and further consideration of the fractionation scheme was required. Author Disclosure: T. Iuchi: None. K. Hatano: None. H. Kageyama: None. T. Imagunbai: None. T. Kodama: None. N. Tohyama: None. S. Yokoi: None. T. Sakaida: None. K. Kawasaki: None. Y. Hasegawa: None.