Canine prostate cancer is an uncommon but aggressive, and often fatal, disease. Prostate cancer can affect both neutered and intact male dogs but usually occurs in older canines. The function of the prostate gland is to supply the fluid that transports the sperm and it lies below the rectum and just behind the bladder. The most common type of canine prostate cancer is carcinoma. This highly aggressive and invasive cancer can rapidly spread to the lymph nodes, bones and lungs. The condition usually goes undetected until the later, more advanced stages are evident. Canine prostate cancer seems to develop without any known cause and can affect any breed of dog.
Symptoms of Prostate Cancer in Dogs
Canine prostate cancer has various signs and symptoms and can resemble those of an enlarged prostate. When the prostate gland becomes enlarged it presses against the wall of the urethra (the tube which connects the bladder to the outside of the dog), making it very difficult for your dog to urinate.
Common symptoms include:
- weight loss
- general pain
- blood in the urine
- blood or pus dripping from the penis
- weakened hind legs
- difficulty and straining while urinating
- constipation and/or difficulty passing stool
- frequent urination
- an arched back while walking abnormally
- fever
- lethargy
Diagnosing Prostate Cancer
Diagnosing prostate cancer is done with urine tests, ultrasounds and contrast x-rays. The absence of prostate specific antigens in dogs makes it difficult to diagnose and determine if the cancer originated in the prostate or elsewhere in the body. Taking a biopsy of the rectal wall is the most definitive method of detection and diagnosis.
Treating Prostate Cancer
Treatment for canine prostate cancer is limited and, in most cases, chemotherapy and radiation therapy are the best option. Surgery on the prostate is complex and can be very dangerous as well as cause complications for your dog such as urinary incontinence. In some cases, anti-androgen drugs are used to fight the cancer, however, most dogs do not respond to these drugs so they have little effect. Having your dog neutered can largely decrease the risk of developing prostate problems such as infections and inflammation; however, it will not prevent dogs from developing prostate cancer. The frequency of canine prostate cancer is similar with both castrated and non-castrated male dogs. Because the disease is not usually detected until it has fully developed, the median life expectancy of dogs with prostate cancer is approximately thirty days. Proper treatment, including chemotherapy drugs with anti-inflammatory agents, may help to extend the life of your dog.