For how long this is happening?
Has he noticed this even when your aren't sexually engaged?
Can you describe the characteristics of this liquid (smell, consistence, color)?

I don't think this liquid has connection with the prostate gland and prostate cancer appears with other symptoms.

A prostate is a gland of the male reproductive system. It is located in front of the rectum and just below the bladder, the organ that stores urine. The prostate is quite small and wraps around a tube called the urethra, which carries urine from the bladder out through the tip of the penis.
The prostate is made up largely of muscular and glandular tissues. Its main function is to produce fluid for semen, which transports sperm. During the male orgasm (climax), muscular contractions squeeze the prostate's fluid into the urethra. Sperm, which are produced in the testicles, are also propelled into the urethra during orgasm. The sperm-containing semen leaves the penis during ejaculation.

This only happens during sex when it happens he says he gets a pain between his testicles and his anus but it does not stay long the stuff that comes out is not alot but he says it is semen he says it smells like it and everything I have not seen it myself he is really embarrassed by this and it does not happen everytime and he also holds back alot stopping ejaculation and if we have sex more than once it usually happens too . thanks ..

Does he feel tension between scrotum and anus?
Can he noticed some changes like abnormal small opening in that area (perineum)?
Has he noticed urinary leakage from the anus?
Does he often suffers from urinary tract infections?

I have the same problem as this lady mentioned.
I am 23 and when I have been working on different methods
of prolonging sex with better stamina.
During sex, when I cum, I sometimes leak through my anus.
It is definitely cum.
I also leak cum or urine often. I have been to many
urologists and none of them can figure out what
is wrong. I've had a prostate check and they said
there was nothing wrong, but I still leak.

I don't feel any pain,
but the symptoms are ruining my life.

Have you experienced frequent UTI's?
Do you have diverticulosis or intestinal inflammatory disease?

Leaking urine or semen from anus can be only experienced if there is a connection between anal canal and urethra. That kind of connection is abnormal and is known as fistula (channel between 2 epithelialized surfaces)

Thanks for responding...
I don't think I've had UTI's because there has been no irritation when urinating, and when I get urine tests there is no bacteria they can find. I sometimes get a weird feeling in the left side of my penis, and left side of my anus, and a weird feeling in my left foot. It's like a muscle cramp in a way, but not very painful.. just enough to worry. I appreciate you responding, you have instilled a little hope where it has been fading.

My husband had diverticulosis and had a major surgery to repair. the surgen said he took a substacial amount of his colon. He has been experienceing leakage from his anus for a short time now, it isn't occuring during strenus times but just standing and he feels like he is sweating there but it isn't sweat.

I have the same problem on I've never checked the smell...yuck...its clear, yet feels as if i'm leaking a little crap at the time right before and during orgasm. I have had roids and polyps, diverticulosis and irritable bowel syndrome...i just figured one of those had something to do with it...sounds as if there is no cure out there?