How much does sex before a blood test affect PSA?

I cut myself off for a week before PSA test. I've read several articles and all said to avoid ejaculation for 48 hours before test. Some doctors said that older men need a bit longer to return to normal after ejaculation. Same with bile riding and having DRE before PSA. My urologist agreed.

I had proton therapy and asked my RO if my prostate would be fried after treatment. He said no, a common misconception. Healthy tissue recovers; cancer does not. He said my prostate may shrink some but otherwise would look and feel much like it did before treatment. When asked about scar tissue, he said there will be parts of the prostate that may feel leathery, sort of like a person who is in the sun a lot.