Dear Daisy Dog
Winston, our eight-year-old boxer, was diagnosed with Sertoli cell tumor. Can you tell us about this kind of testicular cancer?
Testicular cancer is the second most common cancer in male dogs, after skin cancer. One type of testicular tumor is Sertoli cell tumor (SCT).
Interestingly, SCT occurs much more frequently in retained testicles than in testicles that have descended normally.
It can occur in any breed, but boxers, Weimaraners and Shetland sheepdogs are predisposed. Other breeds often affected are collies, Cairn terriers and Pekingese dogs.
SCTs frequently secrete excessive estrogen, so an affected dog may have a pendulous prepuce and enlarged mammary glands. The other testicle is often small, and the prostate may be enlarged. Dogs with SCT usually lose their hair and develop dark skin.
Eighty percent of SCTs are benign, and removal of both testicles usually reverses the clinical signs within three months. Only ten percent of SCTs metastasize to other parts of the body.
While testicular cancer is common, it is easily prevented by neutering dogs when they are young.