Overview of Feline Urinary Bladder Cancer
Urinary bladder tumors are rare in cats, but of the possible cancers, transitional cell carcinoma is the most commonly diagnosed. This is a malignant cancer usually arising from the inside surface of the urinary bladder or urethra and less commonly from the muscular wall of the urinary tract.
The cause of transitional cell carcinoma is unknown, but carcinogens, or cancer causing chemicals, that are excreted in the urine may cause the cells that line the bladder and urethra to become cancerous. Exposure to insecticide dips applied to kill fleas and ticks may increase the risk of developing this type of cancer. Similarly, exposure to sprays used to control mosquitoes in marshy or wetland areas also may increase risk.
Cyclophosphamide, a drug used to treat cancer and certain immune diseases, is metabolized to a carcinogenic chemical called acrolein, which is excreted in the urine. Exposure to cyclophosphamide may increase a pet’s risk for development of urinary bladder cancer.
Female cats are affected more commonly than males and obesity also may predispose to development of this type of cancer.
Urinary bladder cancer is life-threatening. Left untreated, it can result in obstruction of the urinary tract and inability to urinate. This form of cancer can also metastasize, or spread to other parts of the body. At the time of diagnosis, transitional cell carcinoma is estimated to have spread in more than 50 percent of cats in which it is diagnosed. Survival of cats with this type of cancer is dependent on the location of the tumor in the bladder, extent of disease and whether it has metastasized, and what treatments are prescribed. Survival time can range from weeks to more than a year.
What to Watch For
In many cases, these signs can be present for many months before diagnosis. If your pet is showing any of these signs and does not seem to be getting better with treatment, additional tests should be done to rule out cancer as the cause.
Diagnosis of Urinary Bladder Cancer in Cats
Diagnostic tests are needed to recognize urinary bladder cancer and exclude other diseases. Tests may include:
Treatment of Urinary Bladder Cancer in Cats
Your veterinarian may refer you to a veterinary cancer specialist (oncologist) to discuss treatment options. Treatment for urinary bladder cancer may include one or more of the following:
Home Care and Prevention
Evaluation for cancer of the urinary bladder is warranted if you have an older cat and notice blood in the urine, increased frequency of urination, and straining to urinate that either does not respond to routine treatment with antibiotics or that resolves only to return after stopping antibiotic treatment.
You should seek veterinary care immediately if you suspect that your pet is unable to urinate. Inability to urinate leads to severe metabolic complications called uremia within less than three days of complete urinary obstruction.
Watch your pet closely for changes in urinary habits after diagnosis has been made and treatment begun, because such changes may indicate additional tumor growth.
Avoid dipping your cat with flea and tick control products more than two times per year due to possible increased risk of developing bladder cancer. If you live in an area of the country where fleas and ticks are a year-round problem, talk to your veterinarian about alternative forms of flea and tick control.
Obesity may predispose your pet to this type of cancer. Regular exercise and diet control are recommended for the general health of your pet.