Renal Adenocarcinoma in Dogs
Adenocarcinoma of the kidneys is a rare neoplasm in dogs, making up less than one percent of all reported neoplasms in dogs. Similar to other carcinomas, when adenocarcinoma of the kidney does occur, it commonly affects dogs that are older than eight years. There is no breed predisposition in dogs for this type of tumor.
Like other adenocarcinomas, adenocarcinoma of the kidney is very aggressive, usually affecting both kidneys, and growing rapidly and metastasizing to other parts and organs of the body. Another version of kidney adenocarcinoma, known as cystadenocarcinoma, is less aggressive and carries better long-term prognosis. This latter type of carcinoma is more common in German shepherds than other breeds.
Symptoms and Types
The symptoms are mostly non-specific and include:
- Gradual weight loss
- Poor appetite
- Low energy level and lethargy
- Blood in urine
- Exact cause of adenocarcinoma of kidney is still unknown
- Cystadenocarcinoma is an inheritable neoplasm in German shepherds
Your veterinarian will need a thorough history of your dog's health, including a background history of symptoms. The doctor will perform a thorough physical exam on your dog, including a complete blood count, biochemical profile, and a urinalysis to rule out or confirm other causes for these symptoms. Urinalysis remains crucial in the diagnosis of adenocarcinoma of kidneys as it will provide important clues toward the final diagnosis. The presence of blood, proteins, and bacteria in the blood will be determined, and a urine culture will be performed to rule out any infectious causes. Sometime tumor cells are also seen in the urine, which is sufficient for establishing a preliminary diagnosis. Further diagnostics include X-ray and ultrasound imaging, which will demonstrate the presence, size, location and other important information regarding the tumor. If required, your veterinarian will also take a small tissue sample of the kidneys (kidney biopsy) to establish a confirmatory diagnosis. In some cases – as a last resort – surgery may be required to take a sample of the neoplasm for a definitive diagnosis.
There is no single curative treatment for renal adenocarcinoma, but surgery is performed in the majority of cases. Complete resection (removal) of carcinoma tissue, along with some normal tissue, is done. There are some chemotherapeutic agents that may also be used in some patients, but the success rate is quite low. Patients with renal failure or other complications will be treated to prevent further aggravation of symptoms.
Living and Management
As no definitive treatment is available yet, dogs with renal adenocarcinoma may have only a few months to live even if the tumor is small and well-localized. If surgery is performed, your veterinarian will recommend serial urine and blood testing along with radiographs to monitor re-growth of the tumor. Re-growth is to be expected, as carcinomas are characterized by this behavior. Affected patients usually have several complications, like kidney failure, and will need to be monitored on a regular basis. During this time you can improve your dog's quality of life by keeping it comfortable and protecting it from stressful situations. Follow your veterinarian's guidelines, especially in giving chemotherapeutic agents at home. Many chemotherapeutic agents can be hazardous to your health if not handled properly; consult with your veterinarian on the best handling practices.