Does it interfere? It depends upon how bad his cancer was and the treatment he had.
There is a wide range of outcomes.
Let’s say he had his prostate removed. He could still have erections and still have the feeling of orgasm. But he would not be ejaculating any sperm. That has the advantage of no mess, and no chance of pregnancy!
or
He could have had both nerve bundles removed with the prostate and not be able to get an erection in the normal fashion. He might need to use a pump or pills or an injection.
or
He might still have his prostate and is being treated chemically by hormone therapy or cancer drugs, If he is taking drugs to lower his testosterone level to zero he might have no desire or even forget why he thought women were attractive.
or
He could have be treated with radiation which sometimes brings other problems .
or
He could be on active surveillance and worrying about his PSA numbers all the time.

No matter what the treatment, if he still has the desire and can talk, he can participate and both partners can enjoy it.
He won’t be delivering fake porn video squirts but it will still feel good.

He is 55 yrs old. You think he’s done

@honeybun35 It may be a combination of things – maybe his prostate causes a problem, maybe he was tired, maybe he was drained from the night before (literally), maybe he was in a rush due to a meeting, maybe he’s not into sex in the morning, maybe it takes more work for him to “get going” due to any of the issues above. I wouldn’t overthink it.

Maybe he actually had a meeting to go to, and prostate has nothing to do with it.

The prostate supplies the fluid that the sperm uses on it’s way out of the body. So it is important.

Business meetings generally trump getting laid when you’re older and more responsible.

“You done?
Another round?”

I’m surprised he didn’t want, after such romantically stated offer.

@rebbel My first thought as well!!!