The most prevalent tumors of the testicle are Sertoli cell tumors, Leydig cell tumors and seminoma's.

Sertoli cel tumors originate from cells that line the sperm tubes and support the formation of sperm.

Leydig cell tumors originate from interstitial cells near the sperm tubes and produce testosteron.

Seminoma's originate from germ cells in the sperm tubes.

Non-descended testes have higher chances to develop a tumor.

Behavior

At the level of the testes, tumors can develop from different cell types, each of which has its own properties. Depending on which cell type the tumor originates, the tumor can behave differently (e.g. by disturbing the hormone balance). Most of the time, however, a testicular tumor does not cause symptoms and is a coincidental finding. If there are clinical signs, it is the result of metastasis or a disturbance of the hormone balance.

• Sertoli cell tumor. What's special about Sertoli cell tumors is that in 50% of the cases too much estrogen is produced, which can lead to symmetrical bald spots, swelling of the mammary glands, milk production and / or attracting other male dogs to even spontaneous bleeding and a greatly increased risk of serious infections. This tumor spreads in 15% of the cases.
• Seminoma. This tumor mainly only takes up space and spreads in 15% of the cases.
• Leydig cell tumor. This tumor mainly only takes up space and very rarely spreads.

Prevalence

These tumors are most common in older male dogs with a median age of 10 years.

Breed predisposition

A higher risk for the development of this tumor type has been reported for Boxers, Afghan Hound, Weimaraner, Shetland sheepdog, Collie and Maltese dog vs other dogs.

The testes are touched during the routine clinical examination. When irregularities are detected, a rectal examination can be performed to identify further abnormalities such as swelling of the local lymph nodes. The veterinarian can use ultrasound to inspect the abdominal cavity / the testicle and check whether there is an undescended testicle. If this is the case, the veterinarian examines whether it has an abnormal shape and if enlarged lymph nodes are present. Sampling is always recommended in order to make a definitive diagnosis.

Surgery

Removal of the testes and scrotum is always recommended for testicular cancer. If there was a disturbance in the hormone balance, it disappears automatically 1-3 months after the operation. If not, this may indicate the presence of metastasis causing these symptoms to persist.

Chemotherapy and radiotherapy

In case of metastases, chemotherapy or radiation are options, although their effect has so far not been described extensively enough to be able to draw any conclusions.

The prognosis is generally very good after surgery. When the bone marrow is suppressed by a disturbance of the hormone balance, the dog must be monitored very carefully. After all, this bone marrow suppression can be irreversible and life-threatening.