On the proton therapy: As a particle physicist whose best friend just finished (photon) radiation therapy for brain cancer, I know a good chunk about this. First off, not all proton therapy is the same. It's heavily dependent on the linac and gantry a hospital has. UCSF has proton therapy in Davis or somewhere targeting glaucoma and stuff, which is completely different than the facilities at Loma Linda or Massachusetts General. Of higher energy proton therapy centers, there's only about 5 such facilities in the US. As far as general hadron therapy goes, there's none. So a proton therapy center in Washington isn't likely to serve just Washington and/or Baltimore, it's likely to service Virginia, West Virginia, Maryland, New Jersey, and even farther out possibly. On top of that, it's still heavily research based, and moving pretty quickly as we've moved towards modeling human tissue with GEANT4 and Monte Carlo simulations.

Anyway, while I don't know the specifics of the proton therapy centers mentioned, the assumption that a proton therapy center would just service Washington/Baltimore metropolitan areas is silly. After LLNL shut down their proton therapy center/experiment, we don't even have any proton therapy centers in the Bay Area.