腎臟癌在早期可能毫無症狀，當腫瘤擴散到鄰近器官或大部份的腎組織被侵犯時，才會引起疼痛和血尿。針 對早期的腎臟癌治療，手術切除是最主要的根治性治療方式，術後的五年存活率可達80%，另外，對於手術風險 過高而無法接受手術的病人，可以選擇採用局部放射治療。本次我們針對一位腎臟癌術後合併腹主動脈旁淋巴轉 移病人，設計身體立體定位放射治療(stereotactic body radiation therapy, SBRT)，使用醫用直線加速器6 百萬伏特 能量配合整平濾器移除(6 mega voltage flatten-filter free, 6 MV-FFF)光子射束，照射腹主動脈旁淋巴轉移區域，腹 主動脈旁淋巴預計處方劑量45 Gy，分次治療劑量為7.5 Gy，分次治療每兩天執行一次，共計六次，設計體積弧 形調控放射治療(volumetric modulated arc therapy, VMAT)，治療計劃射束由兩圈360 度動態式連續給予。藉由治 療後之追蹤門診評估個案之腫瘤控制率及副作用，追蹤期間沒有發現嚴重之副作用，病人擁有較佳的體能狀態， 對於腹主動脈旁淋巴復發之病人，身體立體定位放射治療是有效的救援性治療。搭配應用影像導引放射治療 (image-guided radiation therapy, IGRT)，可以在每次治療中進行位置誤差之分析並校正，提升治療準確度，增加腫 瘤控制率並降低併發症機率。

Renal cell carcinoma may be asymptomatic at early stage, causing pain and hematuria when the tumor invades neighboring organs or most of the renal tissue. For the treatment for early renal cell carcinoma, surgery is the definitive treatment. The five-year survival rate is up to 80%. In addition, for patients who cannot accept surgery or with high surgical risk, local radiotherapy may be considered. For this patient, we designed stereotactic body radiation therapy (SBRT) to his para-aortic lymph node metastasis after surgical resection of renal cell carcinoma and used a 6 MV-FFF (6 mega voltage flatten-filter free) photon beam by linear accelerator. The prescribed dose to para-aortic lymph node was 45 Gy. The fraction size was 7.5 Gy. The fractionated treatment was performed every two days for total six times. Volumetric modulated arc therapy (VMAT) treatment plan was performed with two arcs of 360 degrees dynamic continuous delivery. Tumor control and side effects were assessed by post-treatment follow-up. No serious side effect was observed during follow-up and the patient had better performance status. SBRT was a effective treatment for patients with para-aortic lymph node recurrence. With the application of image-guided radiation therapy (IGRT), setup error can be analyzed and corrected in each treatment to improve treatment accuracy, increase tumor control rate and reduce the chance of complications.