Cryptorchidism, Canine

Cryptorchidism in Dogs
By Dr. Karen Burgess

What is cryptorchidism?
Derived from crypto- meaning hidden and orchi- meaning testicle, cryptorchidism in pets is the failure of one or both testicles to descend into the scrotum.  Normally, testicles are manually palpable in dogs by 8 weeks of age.  In delayed situations this may occur as late as 6 months.  The missing testicle is typically felt just under the skin along the body wall/abdomen or within the abdomen in which case it is not palpable.

Why would a pet be cryptorchid?
The overall incidence of having a retained testicle in dogs is up to 9%.  While reported in many breeds there are certain predisposed for cryptorchidism (ex. Yorkies, smaller breeds, Siamese cats).  The trait is heritable passed onto from parent to offspring.  For this reason it is not recommended to continue breeding animals that are cryptorchid.

What are the symptoms of being cryptorchid?
Most commonly there are no significant clinical signs of this condition.  The real risk is seen if the retained testicle converts into a tumor which is not that uncommon.  These tumors can cause numerous symptoms including abdominal pain, skin issues, and bone marrow shutdown.  In rare instances the undescended testicle can twist on itself causing a very painful and dangerous condition known as testicular torsion.

How is cryptorchidism treated?
Neutering or castration is the treatment of choice for retained testicles.  Removal of both testicles eliminates future risk of tumor development.  Removal of a retained testicle is technically more difficult at times involving two to three incisions.  Recovery should not be significantly more involved but proper pain management is essential.

What are the risks to not neutering a cryptorchid pet?
The primary risk is development of testicular cancer which is at least ten times greater than in normal dogs.

What is the prognosis with cryptorchidism?
Excellent with early neutering.