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I found some info on testicular tumors in canines/ dogs to share. Let's go over the causes on canine testicular cancer, treatments that are used to cure the dog with testicular cancer, and some photos.

Testicular tumors are considered one of the most common tumors in older intact (unneutered) male dogs. The overall incidence in dogs is not very high because of the large number of dogs that are castrated. However, in intact male dogs these tumors are considered fairly common. The tumors are usually fairly easy to recognize and diagnose. Treatment consists of castration and is usually curative.

Testicular tumors are most common in intact (unneutered) older male dogs. However, they can occur in intact males of any age. There does not appear to be any breed predilection for this tumor. The current cause of testicular tumors is unknown. Dogs that have one or both testicles that are not descended are 13 times more likely to develop a tumor in the undescended testicle than dogs with normal testicles. Except for the increased risk of these tumors in cryptorchid dogs, no other risk factors are readily apparent.

Sertoli cell tumors show symptoms of swelling of the testicular and scrotal area. If the dog is cryptorchid, the swelling will occur in the inguinal or abdominal area depending on the location of the testicle. Up to 50% of the Sertoli cell tumors will produce estrogen and the dog will suffer symptoms of hyperestrogenism. These include an enlarged prostate gland, enlarged mammary glands and nipples, symmetrical hair loss, anemia, and the tendency to attract other male dogs. Sertoli cell tumors may mestasize to the abdomen, lung, thymus, and brain, however, this occurs in less than 15% of the cases. Seminomas will also appear as swellings of the testicle, scrotum, and inguinal or abdominal area. Seminomas produce estrogen or metastasize in less than 5% of the reported cases. Interstitial cell tumors show very few symptoms and do not produce estrogen or metastasize. They are usually incidental findings and not considered to be much of a problem.

Diagnosis is based on history, presentation, and pathological identification through a biopsy or microscopic examination of the removed tumor. Dogs suspected of a testicular tumor should also have abdominal and chest x-rays to check for metastasis as well as a chemical panel and a blood count.

Testicular tumors are easily prevented through routine castration of male dogs. Castration in young dogs prevents aggression, roaming, urine marking, and a variety of other unwanted male behaviors. The surgery is safe and relatively inexpensive, and in the long run saves the owner money. Dogs that are used for breeding can be castrated when they are no longer used for breeding. Dogs that are cryptorchid should always be castrated and the owner should insist that both testicles be removed. Since cryptorchidism is considered to be an inherited trait, cryptorchid dogs should never be used for breeding. Because the retained testicle is 13 times more likely to develop a tumor, it should always be removed.


The following are some photos/ pictures I found of dogs with testicular canine cancer: