What interested me when I was concerned about what treatment I should choose given my trepidation about the side effects of ADT was brachytherapy. I'm cT3b GGIII "at least high risk", according to my RO, so clearly I'm much higher risk than you. A standard treatment often prescribed for cases like mine is some sort of external beam with 2 years of ADT. This was the initial prescription my RO sentenced me to.

I looked into brachytherapy. One of its virtues is that the radiation source is placed inside the prostate, so the full power doesn't pass through any other tissue to get to the cancer. Another virtue is that in many cases, less ADT is required.

My research concentrated on therapies involving external beam plus brachytherapy boost, because my cancer has gone outside my prostate to the seminal vesicles and possibly although not proven beyond. External beam plus brachy delivers a higher dose than is possible with any other therapy, which results in data showing a longer disease free recurrence. The TRIP study showed no improvement with 30 months of ADT compared to 6 months. The highest risk patients were pT3a, not 3b as is the case with me, but I decided on brachy.

Nelson Stone gave a lecture at the 2024 SouthWest Prostate Cancer Symposium about this.
https://grandroundsinurology.com/radiation-dose-and-hormone-therapy-how-much-is-enough/