My 20 month gsd has one retained testicle.   My vet wants to operate to find and remove this.
I am very much against unnecessary surgery.
I would appreciate any comments

There is a higher risk of the retained testicle becoming cancerous.  As your boy is mature you could either have him castrated or just the retained one removed.

Unfortunately as your dog is now 20 months old I would very much doubt that it will come down now, you definitely need to have him operated on.  I usually advise people who are worried about their pups to give it 12 months when they enquire on this site, but I'm sorry at 20 months old your boys won't I don't think.

I understood the poster to be asking whether it was really necessary to have the retained testicle removed.  Does anyone know how much the cancer risk increases with a retained testicle?

According to this article the cancer risk of the retained testicle is 13 times higher than normal.

I'd certainly get the retained one removed, and leave the normal one. Of course, the dog should never be bred from.

That is quite a big risk factor.

Yes it is a high risk that's why I said if it was me I would have it removed now.

My breeder had a male dog who didn't drop till 2 years old- I thought that was quite a long time, no she didn't breed from him.

One bernese i had, had a retained testicle and we had it removed.
We were told the cancer risk was very high if it wasnt removed and he had started with a hind leg limp and didnt wag his tail much.
He was very down and seemed in pain.  Nothing was found on the hind leg x-ray, and while he was under anaesthetic for the xrays of the leg the testicle was removed and he didnt limp again.... he was back to his normal happy self.
I would advise on having it removed.

I knew it would not descend.
Of course I would not breed from him.
He is a very happy healthy dog with no problems.
i just wanted to know what the likelihood of him developing cancer is.
Thank you for all your comments.

Hi there

My vet advised to get it done before the age of 2. I would get both removed.

To OP,

it is best ultimately to have a retained testes removed to prevent future problems - the testes are not designed to be at body temperature and so one retained in the body cavity increases the likeliehood of it becoming cancerous at a later stage.

There is no need to have the normal descended one removed - i.e. no need for full castration should you not wish your dog to develop some of the problems that castration can cause relating to change in temperament, potential feminisation syndrome, unweildy/wooly coat for eg.

At his age it is unlikely to descend (not impossible, but improbable), however there is no urgency to have it removed - I've had specialist advice on this and recommendation is by ages of around 4+ years before it would be regarded as being a "necessary" procedure.  So plenty of time to allow for a larger and slow maturing breed to continue to grow and develop at the optimum rate (that is should you prefer to have complete castration).

HTH, Teri