Treatment and Prognosis of Prostate Cancer in Dogs
Goals of Treating Prostate Cancer
Prostate cancer is an extremely serious disease in domestic dogs. Unless caught very early, it almost certainly will become locally invasive and will spread to distant locations as well. The primary goal of therapy is to eliminate or at least reduce the chance of progressive metastatic disease by surgically removing the prostate gland. Unfortunately, in almost all cases, the cancer has spread by the time it is diagnosed. If surgical correction is not a viable option, palliative treatments are available to provide relief from the symptoms that accompany prostate cancer, and to thereby help affected dogs live as comfortably as possible for the duration of their lives.
Surgical resection of all cancerous tissue is the only way to cure prostate cancer. This is only possible if the cancer has not metastasized. If surgical removal is not possible, radiation and chemotherapy can be used to help minimize the adverse effects of the disease.
Surgical options include partial or complete prostatectomy (removal of part or all of the prostate gland). This procedure may or may not preserve the urethra, depending upon its involvement. The urethra is the anatomical tubular passageway between the bladder and the outside world, through which urine is excreted. In male dogs, the urethra also is the passageway for discharge of reproductive secretions. If the urethra is severed or removed, a cystostomy tube must be placed so that the dog can urinate. Because prostate cancer is so highly metastatic, most veterinarians recommend chemotherapy and/or radiation therapy as adjuncts to surgery.
“Palliative” means providing relief. Palliative therapeutic options are available for dogs whose prostate cancer has spread, as well as for dogs with local infiltration of cancerous tissue that for whatever reason is not suitable for surgical removal. The primary goals of palliative treatment for prostate cancer are to relieve pain and to preserve the patency (openness) of the patient’s urethra.
One form of palliative therapy is chemotherapy – which is the use of drugs to treat disease. Chemotherapy has proven to be effective in treating many types of cancer in dogs. It is, however, expensive and may only be offered by veterinary oncologists in specialized treatment centers and veterinary teaching hospitals that are not easily accessible to all owners.
Another form of palliative therapy is the use of radiation, either in addition to or instead of chemotherapy or surgery. Radiation usually is administered in small doses over several weeks.
Canine prostate cancer is extremely aggressive. Even after treatment, affected dogs should be monitored regularly by a veterinarian for signs of metastasis. Unfortunately, because this disease is so prone to spreading both locally and afar, dogs with clinical signs caused by prostate cancer have a guarded to grave prognosis. Medical management may help to prolong a dog’s quality of life. However, euthanasia is a realistic consideration for owners of dogs with prostate cancer, especially once it has metastasized. Only a veterinarian, in consultation with the owner, can determine the best course of treatment for these dogs.