Health Risks Related to Undescended Testicles on Dogs

Testicular Torsion

• Testicular torsion is a condition marked by the twisting of a testicle on the end of its blood supply and spermatic cords. The testicle loses oxygen and blood and swells, backing up with lactic acid and carbon dioxide, a process noted in "The Clinical Textbook for Veterinary Technicians." This painful condition can occur in dogs with normal testicles, but appears significantly more often in cryptorchid dogs as noted in "Clinical Endocrinology of Dogs and Cats." This is because descended testicles are held tightly in place by the scrotal sack, while cryptorchid testicles have a greater range of motion within the body. The symptoms of testicular torsion in a cryptorchid dog include abdominal pain, unwillingness to eat, lethargy, panting, pacing, vomiting and crying when touched. If left untreated, the testicle will rot and die, causing severe inflammation of the abdomen, fluid retention, vomiting and shock. Treatment involves removing the testicle and the administration of pain relief and supportive care to the dog.

Testicular Cancer

• Dogs with undescended testicles are at a 13-percent higher risk for developing testicular cancer than their normal counterparts, who already have a 10-percent risk for developing the disease if the testicles are left intact, as noted in "Arthur's Veterinary Reproduction and Obstetrics." Steroli cell tumors, seminomas and Leydig cell tumors are the three most common forms of cancerous growths found in cryptorchid dogs according to "Cancer in Dogs and Cats: Medical and Surgical Management." Steroli cell tumors occur when the cells that help spermatozoa mature mutate and replicate. Seminomas are cancerous growths stemming from mutated cells that produce sperm. Leydig cell tumors occur when the cells that regulate and produce testosterone mutate and replicate. Steroli cell tumors and seminomas can both grow to the size of a basketball if left unchecked as noted in "The Clinical Textbook for Veterinary Technicians." Both tumors also have a high possibility of spreading to other organs, or metastasizing. Leydig cell tumors are typically benign and rarely metastasize. Visible tumor growth, abdominal pain and bleeding, organ dysfunction, infection, shock, weight loss and death are symptoms seen in dogs who develop cancer in undescended testicles. Castration and supportive care are the recommended treatment options for these dogs.

Excess Estrogen

• Steroli cell tumors create estrogen, a hormone typically found in low quantities in males. The excess production of estrogen can cause a dog with an undescended testicle to act and appear more feminine. The dog's mammary glands grow larger and the dog's skin and coat may darken. Hair loss occurs over the dog's body. Dogs with too much estrogen as a result of an undescended testicle lose their libido and may change their behavior when urinating, squatting instead of lifting their legs. Estrogen toxicity is possible in cryptorchid dogs, causing prostate problems, anemia and bone marrow hypoplasia, where the bone marrow cells die and are unable to produce red and white blood cells. "Arthur's Veterinary Reproduction and Obstetrics" recommends castration and supportive oncological care.

Excesss Testosterone

• Dogs with undescended testicles may produce more testosterone than their normal counterparts, especially if they develop Leydig cell tumors. Dogs with too much testosterone experience an increased libido and an increase in aggression and predatory behaviors according to "The Clinical Textbook for Veterinary Technicians." This leads to prostate problems, perianal tumors and sexual dysfunction. Castration and supportive care are recommended for cryptorchid dogs with too much testosterone.