Radiation Protocols and options!

Hi everyone! I recently had a lumpectomy for DCIS, grade 3 with comedo necrosis, the tumor was 1.75cm. I am being treated at MD Anderson, love my surgeon and my nurse. I decided to receive radiation which I really don't want, but I'm doing this since my tumor was high grade. My current concern is with the radiation oncologist. At first, she said she would do either partial breast radiation (33% or less of the breast) or whole breast radiation. Due to my medical history and my family medical history I do not want my heart, lung or ribs in the picture. That is really not ok with me. I met with her again after surgery. I had been considering being transferred to a different doctor as I felt my first meeting with her didn't go so well. I met with her Monday and it went very well and she agreed to give me basically almost a whole breast radiation that left out the organs and ribs. I felt much better. A problem arose when I went for the SIM today, the subject came up again and she told me she could leave the heart out of the field but a little bit of the lung and ribs will be radiated. I am very uncomfortable with this. I spoke up and tried to do this nicely but I could see she was frustrated and I did not feel supported. Instead of leaving there feeling comfortable today, I feel dis-ease. I sense that the hospital has research protocols affecting my treatment. On one hand, she wants me to have whole breast radiation, rather than partial, but at the same time it seems like I am struggling (almost fighting in a way) to get radiation that leaves out my organs and bones which may be slightly less than whole breast radiation. I really wish I was able to leave there feeling more supported today. I'm wondering if anyone else is struggling with this issue, and if so, how you dealt with it? I appreciate any help you can give me. This is a frightening process and I am scheduled to review the plan and start radiation next week. I hope I'm able to move forward. Thank you.