If I were you, I'd contact UFHPTI in Jacksonville and send for their free packet of information. If you end up going to Florida, or Loma Linda in California, think of it as a "radiation vacation." If you live up north, go in the late fall/winter. Many do. Sorry you have an Advantage Plan, but UFHPTI can tell you immediately if they've worked well or not with your insurance carrier. Many oncologists have neutral or negative opinions of proton therapy, apparently, but most of those have zero experience treating patients with it, according to Dr. Gary Larson, an oncologist who has treated patients with both photon and proton therapies. If you Google Larson, you'll find him here: https://integrishealth.org/doctors/gary-larson. Here's an article he posted online: https://www.quora.com/What-are-the-best-treatment-options-for-prostate-cancer/answers/19334097 .