@jcbagley
The addition of being on a blood thinner is a compounded factor. I was on aspirin but was taken off it 2 weeks prior to space/oar and radiation treatments. I then stayed off it for several weeks after. This was per my R/O at UFHPTI. They also took me off on certain supplents and vitamins I was taking.

I will pass on what was told to me by UFHPTI R/O. Even with space/oar (which helps more colon away from prostate) you will probably still get radiation damage to colon as most R/Os will treat what the call margins which is beyond the prostate.

There are tiny blood vessels in the colon. They are easily damaged by radiation. The body will start to replace them but the new tiny vessels are very fragile and easily damaged by constipation etc. Thus it is common to get some bleeding from these new vessels from damage but over time they will get stronger.

You are on a blood thinner. So any bleeding would be compounded by that.

I had minor bleeding (not much more than a spot on tissue) that came several months after treatment ended. It slowly got better and better. Some don't get any bleeding at all and some a lot worse.

From the options given you. You will see posters mention the high dose is usally only a 5 dose over two weeks. I have not heard of some many days of treatment with high dose you were given.

The low dose can be a different number of days but usually is around 30-40 from what I was told and what I have read on MCC. My PCP stated to me (he does a lot of research) that statisics are showing an increase in side affects with the high dose. I guess very long research will reveal informative statistics for patient information.
Good luck!