Testicular Tumor (Sertoli Cell) in Dogs

Testicular tumors are common in canines. Tumors are often seen in dogs who have one or both testicles undescended, which is known as cryptorchidism. Studies have proven that canines with cryptorchidism are predisposed to testicular neoplasia. Sertoli cell cancer in dogs who have the condition of undescended testicles is associated with 60% of documented cancer cases. There are also other factors that may contribute to Sertoli cell cancer, like injury to the testicles and exposure to toxins. As well, there is a breed disposition to testicular cancer in dogs, and further predisposition to each type of this cancer (Sertoli cell, Interstitial, and Seminoma). Cure and resolution are possible, but early and aggressive treatment is imperative. If your pet is acting as if he is ill, or if you notice an irregular growth or mass on your pet, be certain to make an appointment with your veterinarian.

In the testes, the Sertoli cells function within the seminiferous tubules, aiding in testicle formation. In addition, they nourish the spermatozoa. A Sertoli cell tumor expands and grows, destroying the surrounding organ tissue.

A canine who has developed a Sertoli cell cancer of the testicle may exhibit the following signs of the condition.

• There may be blood in the urine (hematuria)
• There could be shrinkage and then an atrophy of one or both of the testicles
• In addition, there could be an atrophic penis
• Your pet may lose weight
• He could appear pale
• There may be hair loss in the area of the tumor (alopecia)
• There could be hyperpigmentation of the skin
• There could be a mass in the abdomen or inguinal area
• Your dog could have characteristics of feminization such as having an attraction to male dogs or a flow of liquid from the breasts

Types

There is a breed predisposition to testicular cancer. Specifically, Airedale Terriers, Weimaraners, Pekingese, Shetland Sheepdogs, Fox Terriers, Norwegian Elkhounds, and West Highland White Terriers are prone to the Sertoli cell testicular tumors.

As in humans, the exact reason why our pets develop cancer is unknown. What is known is that there are factors that can contribute to the growth of cancerous cells.

• Genetic predisposition
• Hormones
• Exposure to chemicals
• Exposure to toxins
• Frequent inflammation and swelling of the testicles
• Injury to the testicles
• Age (the average is 8 to 10 years of age, except in dogs who have undescended testicles which is called cryptorchidism)
• The Sertoli cell tumor is associated with hyperestrogenism (hence the feminization often seen in dogs with this cancer)

When you bring your pet to the veterinary clinic, the visit will begin with a physical examination including a palpation of the scrotum and a rectal exam to check the lymph nodes in that region, as well as the prostate. While the veterinarian is performing the physical part of the diagnostic procedure it is a good time to discuss symptoms that you may have seen in your pet. Any changes you have noticed in your canine’s regular day to day activities, variations in appetite, or other signs that have led you to suspect that your dog is ill are important and helpful for the veterinary team to know.

Standard testing that can provide an insight to your pet’s health condition are blood tests and urinalysis. There may be a presence of blood in the urine. Markers in the blood that will indicate a problem are anemia, leukopenia (decrease in white blood cells), increased estrogen levels, and thrombocytopenia (low platelet count). Your veterinarian may want to see a sperm sample because abnormalities will be another indication that testicular cancer is a possibility.

Radiographs (X-rays) of the chest and abdomen may be ordered, in addition to ultrasonography of the testes (to look for irregularities). An ultrasound of the abdomen could also reveal that the testes are not descended and may be seen in the inguinal canal or the abdominal cavity. Finally, there could be a need for needle aspiration or biopsy, though these tests may be done only if absolutely necessary as they are rather invasive.

The treatment for a testicular tumor involving the Sertoli cell is removal of one or both of the testicles. This method of treatment has been documented as the most effective way to eradicate the cancer and is called an orchiectomy. If the cancer has not metastasized, the prognosis for your pet is good. The  signs of feminization that accompany this type of tumor will most likely regress within 4 to 8 weeks. If it does not improve by 4 to 5 months, this could indicate a metastatic spread that was not evident previously.

Your furry family member has a good chance of recovery but keep in mind that he will need special care when he returns home the hospital. Instructions may vary depending on what type of surgery he had (for example inguinal testes removal or straightforward castration). Your pet will have to rest and go on leash walks only, in order to protect the site of the surgery and to prevent postoperative bleeding. You will need to keep the area clean and check daily for signs of bleeding or swelling. Your veterinarian may recommend that your dog wear an Elizabethan collar to prevent him from licking the surgical area. Pain medication and anti-inflammatories will be prescribed to keep your pet comfortable and in a good state of mind enabling him to rest over the next several days. Contact your veterinarian with any concerns that you may have about the incision, or if you have questions about his recovery throughout the convalescence process.