2016年衛生署公布去年國人十大死因，惡性腫瘤連續蟬聯十大死因之首，且死亡率有逐年増加的趨勢。其中女性發生率前十大癌症之首為乳癌，而本科治療案例以乳癌居多。強度調控治療技術(Intensity moderate radiotherapy, IMRT)，是利用多葉式準直儀及逆向治療計畫計算系統(inverse planning system)的配合，調控每一入射射束通量，藉由射束強度變化調整，可更準確的給予所需的劑量在腫瘤體積上和降低正常組織併發症的機率，此為目前放射線治療普遍使用的治療技術。在2008年後推出弧形強度調控放射治療(Volumetric Modulated Arc Therapy, VMAT)與IMRT相較，此技術更精準、更有效率的提高腫瘤治療劑量，更進一步提高腫瘤控制率，同時也能保護到周圍的危急器官，並進一步降低正常組織併發症發生率，減少其副作用。因此本研究採取20例左側乳癌術後放射治療計畫之記錄與影像，分別利用IMRT使用七個角度、九個角度及VMAT一個弧形、兩個弧形之治療技術做比較，用此四種技術分析放射線對腫瘤的包覆度、順形度、均勻度、劑量分佈、治療時間、正常組織的保護能力，從四種技術挑選最適合，並有益於病人之治療計畫。因此利用本研究得知結果，挑選出最適合本科乳癌病患之治療技術，希望能善加利用此四種技術造福病患。

In 2016, the Department of Health announced the top ten causes of death among people last year. Malignant tumors were the first to cause the top ten causes of death, and the mortality rate has increased year by year. Among them, the top 10 cancers among women are breast cancer. Intensity moderate radiotherapy (IMRT) is a technique which uses MLC and inverse plan system to moderate every input beam flux via intensity alteration. The technique can deliver the dosage of tumor volume more accurate and decrease the complication rate of normal tissue. The technique is commonly used in radiotherapy. After 2008 launched volumetric modulated arc therapy (VMAT). Compared with IMRT this technology can increase the tumor treatment rate more accurately and efficiently and further improve the tumor control rate. Simultaneous protection around Emergency organ. Further decrease normal tissue complication rate and decrease in side effects. This technology can increase the tumor treatment rate more accurately and efficiently and further improve the tumor control rate, and protect the surrounding critical organs and further reduce the incidence of normal tissue complications and reduce side effects. Therefore, this study used 20 records and images of postoperative left breast cancer radiotherapy planning. Respectively, comparison of IMRT using seven angles, nine angles, VMAT single arc and VMAT duel arc technical of treatment. This analysis using four techniques: tumor coverage, conformity, dose distribution, treatment time, protective ability of normal tissues. From these four technologies selection is optimal and beneficial to patient's treatment plan. Therefore, use the results of this study. From selecting the most suitable treatment technology for undergraduate breast cancer patients. I hope to make good use of four technologies to benefit patients.