Cancer of the urinary bladder is uncommon in dogs, but if it does occur, it is most often a type of cancer called transitional cell carcinoma (TCC). Because it is generally not diagnosed until it is well advanced, treatment is often unsuccessful.
Which dogs are at risk to develop bladder cancer?
Transitional cell carcinoma in dogs is more common in older females. Scottish terriers, West Highland White terriers and Shetland sheepdogs appear to be at higher risk. One study found that Scottish terriers exposed to herbicides were at far greater risk of developing this bladder cancer than those that were not exposed.
Are there different types of bladder cancers?
There are multiple types of bladder cancers. Some may start out in the bladder and others may have metastasized to the bladder. The most common bladder cancer in dogs is transitional cell carcinoma (TCC).
What are the symptoms of bladder cancer in dogs?
Dogs with bladder cancer often have blood in their urine, strain to urinate, have painful urination, and urinate often. The dog may have recurrent urinary tract infections. Transitional cell carcinoma can sometimes spread to the bone, in which case the dog may appear lame. If the cancer is causing a blockage of urine, the dog may also vomit, not eat, and act lethargic.
How is bladder cancer in dogs diagnosed?
The symptoms of bladder cancer are virtually the same as those seen in dogs with urinary tract infections or bladder stones, so bladder cancer must be distinguished from these other diseases. The dog's abdomen will be palpated and a rectal exam will be performed. The bladder tumor may be identified through these procedures. Ultrasound examination and special radiographs (x-rays) of the bladder may make it possible to visualize the cancer. In addition, it is necessary to obtain cells (a biopsy) from the tumor and examine them microscopically to make a definitive diagnosis. Ultrasound and radiographs of the chest are taken to look for metastasis (spread) of the cancer. A complete blood count, chemistry panel and urinalysis should be performed, as well.
There is a blood test called a V-BTA test that is used to screen for transitional cell carcinoma in dogs. The test is not perfect, however. If the test result is negative, one can be fairly confident that transitional cell carcinoma is not present. If the test is positive, cancer may be present, or the positive test could be due to other disease conditions.
What is the treatment for bladder cancer in dogs?
Unfortunately, transitional cell carcinomas usually have become quite large by the time they are diagnosed, and because of their location in the bladder are very difficult, if not impossible, to remove. Removal of the entire bladder (cystectomy) has been performed in some cases.
Multiple types of chemotherapy have been used to treat this cancer, but the response is generally not as good as with some other cancers. Chemotherapy may be combined with the use of a drug called piroxicam, which is a nonsteroidal anti-inflammatory drug (NSAID) that can greatly improve the quality of life for dogs with transitional cell carcinoma of the bladder. Radiation therapy has been used on some occasions, but side effects affecting urination have caused complications.
What is the prognosis for dogs that develop bladder cancer?
Unfortunately, most dogs with transitional cell carcinoma of the bladder will eventually die of the disease. Survival times are usually longer for dogs without metastasis of the tumor.
How can bladder cancer be prevented?
Although there are multiple factors that may be associated with the development of bladder cancer, herbicide exposure is one that can be prevented.