Can salvage radiation therapy be safely and effectively completed in less time?

While SBRT has reduced the time it takes for primary treatment (at least for low and intermediate risk, so far) to a mere 5 treatments, salvage or adjuvant radiation still takes about 7 weeks worth of treatments. Some recent studies suggest the treatment time can be shortened without sacrificing safety or effectiveness. Read about it here:

Can salvage radiation therapy be safely and effectively completed in less time?

- Allen

We will probably never have that data, because if it arises, it would arise more than 10 years in the future and such studies seldom go that long. All we know is that it does not seem to be much of a problem. Some estimates are about five excess malignancies per thousand treated by radiation. Hypofractionated treatments discussed in the article may be less than that because of the higher accuracy needed, and the lower total absorbed dose.

Squirm,
I've never heard of protons being used for adjuvant or salvage. I've only ever heard of protons being used on the prostate itself. I would think it would be too precise for the job at hand, just as SBRT might be.
- Allen