There was an article about IMPT (Intensity Modulated Proton Therapy) in the Journal of Oncology about a year and a half ago. It mentioned MD Anderson as one of the places that uses it, in fact has an entire building donated to it's use. The article described it's advantages over say IMRT in that it is like a smart bomb. It can be programmed to seek out a specific tumor and actually conform to its internal shape and "explode" inside killing the tumor but sparing surrounding tissues. The article was a BIT more technical than my summary. It's uses are obviously suited for hard to reach tumors as in the brain or other sensitive areas but as Brain says it would not be suited for an area as great as most of us have to have radiated. I kept that magazine around in my office forever and now I can't find it!!