@spaccer I can't answer the scar tissue question other than scar tissue can be created with treatment from radiation as my radiation oncologist told me I had to use another method of treatment if I ever get a biological re-occurrence.

I too, had a 3+4 Gleason and an 11.2 psa. I had 5 treatments with the Mridian radiation machine which has a built in MRI (vs fused images). The margins treated around the prostate are much less because of the built in MRI (2 mm) vs 3-5 mm with other types of radiation machines. This means less healthy tissue is exposed. If you are thinking of radiation, check out the Mirage randomized trial which showed a significant difference in side effects and toxicity because of the built in MRI.

Here is an article from Urology Times talking about it:
https://www.urologytimes.com/view/mirage-trial-margin-reduction-with-mri-guided-sbrt-reduces-toxicity-vs-ct-guided-sbrt