High brightness electron beam for radiation therapy: A new approach

I propose to use high brightness electron beam with 1 to 100 MeV energy as tool to combat tumor or cancerous tissues in deep part of body. The method is to directly deliver the electron beam to the tumor site via a small tube that connected to a high brightness electron beam accelerator that is commonly available around the world. Here I gave a basic scheme on the principle, I believe other issues people raises will be solved easily for those who are interested in solving the problems.