目的：評估放射線治療應用於肝細胞癌合併下腔靜脈腫瘤栓塞之成效，及預後因子。 方法：於 2006 年至 2009 年間，共 22 位肝細胞癌合併下腔靜脈腫瘤栓塞之病患接受放射線治 療。放射線劑量為 60 Gy，分 30 次給予。使用強度調控放射線治療技術。 結果：有 7 位病患達到完全反應，6 位病患達到部分反應。整體 1 年存活率為40.9%，2 年存活 率為 22.7%，中值存活期為 8 個月。對放射線治療產生客觀反應（包括完全反應及部分反應） 為唯一有意義之預後因子。有客觀反應之病患之 1 年存活率為 53.8%，中值存活期為 16.9 個 月。無客觀反應之病患之 1 年存活率為 22.2%，中值存活期為 4.7 個月（p= 0.004）。 結論：對於肝細胞癌合併下腔靜脈腫瘤栓塞之病患，放射線治療可以扮演緩解治療的角色。

Purpose : To evaluate the role of radiotherapy in treatment of hepatocellular carcinoma (HCC) with inferior vena cava tumor thrombosis (IVCTT) and the prognostic factors for overall survival. Materials and Methods : Twenty-two patients with HCC and IVCTT referred for radiotherapy between 2006 and 2009 were retrospectively reviewed. A total of 60 Gy in 30 daily fractions was delivered with intensity-modulated radiotherapy techniques. Patient-related and treatment-related factors were analyzed to evaluate their prognostic significance for overall survival rate. Results : Complete response was noted in 7 patients and partial response in 6 patients. The 1-year, 2-year overall survival rates were 40.9 %, 22.7% and the median survival was 8 months for the entire cohort of patients. Objective response (complete or partial response) to radiotherapy was the only prognostic factor for overall survival. For patients with objective response to radiotherapy, the median survival was 16.9 months and the 1-year overall survival rate was 53.8%, compared to 4.7 months and 22.2% of those without objective response (p =0.004). Conclusions : Our results showed that radiotherapy achieved a high objective response rate and prolonged survival in patients with HCC and IVCTT. Patients with response to radiotherapy have favorable prognosis than their counterpart. Radiotherapy could be considered as an effective palliative treatment option for patients with HCC and IVCTT.