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Testicular Cancer in Dogs

Testicular cancer occurs in un-neutered male dogs.

Testicular tumors occur in male, un-neutered dogs. Most of the time, testicular cancer is malignant, which means it is aggressive and may spread throughout the body. However, it generally occurs later in the dog's life, and metastasis to organs doesn't happen in most cases.

Signs of Testicular Cancer in Dogs

Dogs with testicular cancer usually have one testicle that appears larger and feels different than the other. The tumor is often painful, so the dog doesn't like having it touched.

Some dogs may show other signs of cancer also, such as lethargy, weight loss, and excessive skin bruising.

The Case of Cryptorchidism

When a dog has one testicle that doesn't descend into the scrotum normally but stays up on the abdomen, testicular cancer can occur in the retained testicle. In fact, testicular cancer is more common in retained testicles. In that case, the testicle isn't visible so enlargement won't be noticeable. The cancer may progress further in that case before it is diagnosed.

Learn more: "Cryptorchidism: Retained Testicles in Dogs."

Diagnosis of Testicular Cancer in Dogs

Your veterinarian will do a thorough physical exam of your dog, including the testicles. If there is a cancerous retained testicle, the doctor may feel it in the abdomen or identify a painful abdomen.

X-rays can help identify metastasis or retained testicle. An abdominal ultrasound may also be helpful in the diagnosis of cancer in a retained testicle.

Treatment of Testicular Cancer in Dogs

Castration, which is surgical removal of the testicles, is the first thing to do when testicular cancer is identified. In the case of a retained testicle, the surgery is intra-abdominal. Depending on whether there was metastasis of the tumor, further treatment such as radiation or chemotherapy may be necessary after surgery.

Prevention of Testicular Cancer in Dogs

Testicular cancer is entirely preventable by having the dog neutered at an early age. If a retained testicle is identified in a puppy, abdominal surgery should be done to find and remove it as soon as possible.

You May Also Like These Articles:

Cryptorchidism: Retained Testicles in Dogs

X-Rays in Dogs: What Can They Tell Your Vet?

Ultrasound: What Is It and When Do Vets Use It?

Dog Neutering: Is Earlier Better?

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