Bens,
Yes, Stereotactic Radiation Therapy guided by real time MRI is in my opinion the correct approach. The Proton Beam version versus Photon Beam version is the only difference between what your brother is receiving and myself. The long term studies on the newer Proton Beam are not yet available. This process MAY provide a more targeted approach... but both appear to be highly efficacious for early stage prostate gland cancer treatment. The Proton approach is not as widely available as of yet.