I must agree with all of the above - your stats look like you have caught it early (would be good to have your PSA), but at 56 you will probably have to deal with the Pca in your lifetime. Meanwhile, it isn't just sitting there doing nothing - it may be slow growing, but it is growing.
Proton therapy is a noninvasive treatment using proton beams - it differs from regular radiation (IMRT, IGRT, etc) which uses XRay. Proton has no exit energy, the bulk of the beam being deposited at the tumor site, so the damage to healthy cells is minimal. There are several threads on proton on Bluebird's "Helpful Hints" thread. Also, can get info at www.protonbob.com.
This forum is a wealth of info and help, so continue to research and good luck to you. Keep us updated.