Dr. Jeff Forman (whom used to be at Karmanos Cancer Inst.-also where DMC-Detroit Medical Center is and affilated with Wayne State Univeristy group), is a pioneer in using (in selected patients whom saw the choice offered), 2-machines separately and two rays used and published his own patients findings over a period of years, the ones whom got Neutron(Cylcotron machine)perhaps 10 sessions followed by Photon(IMRT machine) perhaps 24 sessions, thereafter had better survival and/or time to recurrance. Neutron ray is rarer than Proton as you have to have a huge Cyclotron machine available, maybe 3 total in the USA right now. Also you need a doc skilled at using this ray, which is more powerful and works little differently than Proton or Photon rays. Dr. Strum talks about
these rays and how they work and comparison data in his book A Primer on Prostate Cancer, so it is interesting indeed as what is out there. If a patient is considering radiation as his first and primary overall treatment and has excluded brachy seeds for some reason, look closely at your radiation choices and in your case you may need or wish to get the more potent protocol or even highest doseage on IMRT (photon). Costs of these protocols is expensive and is something else to look at, if you have excellent insurance probably no problema mi amigo.
Alot of things for patients to consider even in salvage therapies, ask alot of questions that may help you.