Are men able to have genital sex if they no longer produce any testosterone?

I suppose you can rub noses together or something like that, but that ain’t sex. Sex involves genitals, by definition. See where I’m goin’ with that?

Plenty of acts involve only one person’s genitals, and some don’t involve either.

I do see where you’re going, and it’s a wide highway you’re on, but if you don’t have a car, you can get there on the bike path eventually. Metaphorically.

Playing footsies might lead to sex but playing footsies is not a sex act or is it now?

It depends on what kind of connection your footsies make with your brain(sie).

I suspect there’s going to be a gap in understanding here between people who’ve had to deal with aging and disability and people who haven’t.

oh.

Perhaps I’d call footsie braingasms intimacy. Or sex?

Making love, it doesn’t need a definition

Before my surgery the surgeon inserted a spacer between the prostate and the rectum, possibly for this reason. In any case, I’m old enough so that odds are I’ll be dead in 20 years anyway.
I told him my father never had prostate cancer, his response was that he probably did and just never realized it.
I believe there are other risk factors, none of which I had. My family is not very cancer-prone. All the cancer I know of stemmed from a clear cause, like smoking (my aunt) and a radium hysterectomy (my grandmother, and they did those 100 years ago.)

You’re getting there! If genitals are not involved, it ain’t sex! This should not be contentious.

I would be interested in hearing your definition of sex, without either sexual organs being involved?

Most people would consider anything that leads to orgasm to be sex. And orgasm doesn’t necessarily involve genitals being stimulated.

Not that actually going all the way to orgasm is required for sex, either. You obviously can not orgasm during genital stimulation. But there are also other erogenous zones, and then the whole thing with fetishes and kink.

If it feels the way sex feels, it’s still sex. If you’re both aroused and satisfying the sexual urges of your partner, that’s sex.

For instance, there are a lot of variations on anal insertion.

A gay friend with an older partner said, “it’s possible to have an orgasm without getting an erection. It’s less satisfying, but it’s totally possible”.

What i find astonishing is that his doctor didn’t discuss this with him up front. A more common sentiment is “my doctor said i wouldn’t be able to have sex, he didn’t tell me that i wouldn’t mind.” Because a lot of people lose their libido when they are cut off from testosterone.

But your friend still wants to engage in sex. I’d like to second @NinthAcolyte 's recommendation of a vibrator, which they can use together on both of them.

If he wants the piv experience, he should also discuss options with his doctor, like an implant.

Besides injections, another method of increasing testosterone levels is testosterone gel, which you (at least for some people) apply by rubbing it into your shoulders, but obviously the friend mentioned in the OP should talk to the doctor about it.

Someone using a strap-on to anally penetrate their partner.

This is what I use and it brought my testosterone levels up from almost 0 to right in the middle of the normal range.

But it sounds like the guy is intentionally reducing his testosterone to treat his cancer, so I think that suggestions that don’t require more testosterone would be more helpful to him.

Gentlemen (and others with prostates), get a blood test every year to check your PSA level. If it gets elevated, it’s a sign of prostate cancer. The sooner you catch it, the better.

Are erection-inducing drugs like Viagra not an option for the OP’s friend? Or do those require testosterone to work?

They won’t work if you have low testosterone.

It may be a sign of prostate cancer. More often it’s not, for mild elevations. But yes, regular screening is important, that’s how my aggressive prostate cancer got found early.

It’s quite contentious, as your statement is not considered correct by medical experts. Consensus is that sex happens in the brain. While involving the genitals is by far the most common way of having sex, many individuals have arousal and orgasm from stimulation of other areas such as the breasts, nipples, buttocks, nape of the neck, anus, and misc. other regions uninvolved in reproduction.

This is not new. It was being taught at the Johns Hopkins Medical Institutions department of Human Sexuality in the 1970’s.