There are 3 kinds of testicular cancer – Sertoli cell, Seminoma and Intestitial cell. The treatment for all is identical – castration. Although cancers are unlikely to spread they do carry problems so should be removed – the testicle may swell (considerably in some cases) & cause discomfort or it may secrete female hormones and cause feminisation – hair loss, enlarged nipples, weight gain.
Cryptorchid males (those without 2 fully descended testicles in the scrotum) are more likely to develop testicular cancer and should be castrated as a routine befoe the age of 3-4yrs.The retained testicle(s) are 13 times more likely to develop cancer. It is too warm for testicles in or next to the body – they like to be a few degrees cooler in the scrotum. Cryptochid males should never be used for breeding as it is considered an inherited trait. I am not aware of cryptorchidism being a significant problem in the Vizsla.
Entire males should have their testicles routinely checked – just have a gentle feel around – they should be approximately even sized and a firm texture. In most testicles the knobbly vas deferens can be easily felt and is often mistaken for a lump – just have a good feel of the other one & if both are the same there is unlikely to be an abnormality. Sometimes the lump cannot be felt but you may notice the signs of feminisation – in which case seek the advise of your vet. Some entire males with prostate or anal gland problems may have excess testosterone which could be caused by neoplasia. Most vets will routinely check well behaved entire males during vaccination or clinical examinations – if you have any doubt just ask them have a feel!!
Testicular tumours are easily prevented through routine castration (I know – not a very popular suggestion to most breeders.) Dogs that are no longer used for breeding could be castrated and there are other advantages of castrating dogs that are never going to be used for breeding. (No testicular cancer and a massive reduction in the incidence of prostate problems, perineal hernias, anal adenomas and anal gland problems.)
Just remember to include a quick feel around the scrotum when checking your older boys.