Transitional Cell Carcinoma in Cats

Transitional cell carcinoma (TCC) is a type of type of cancer that affects the lining of the urinary tract system called the transitional epithelium. Transitional cell carcinoma is malignant and metastasizing, which means that it can spread aggressively through other parts of your cat’s body. This type of cancer will often spread to other areas of the urinary tract such as the kidney, ureters, urinary bladder, urethra, prostate or vagina. As it spreads, transitional cell carcinoma can cause a great deal of pain for your cat by creating blockages in the kidneys, urethra, or other affected organs.

Due to the location of tumors in the urinary tract areas, symptoms of transitional cell carcinoma will typically begin with your cat’s urination habits. Symptoms may include:

• Inability to urinate
• Difficulty urinating
• Urinating in small amounts
• Urinating in inappropriate places or unexpectedly
• Loss of bladder control
• Blood in urine

It’s important to note that many of the symptoms of TCC can mimic less serious conditions such as urinary tract infections. One of the key differentiating factors between transitional cell carcinoma and these other conditions is that in cats with transitional cell carcinoma, the symptoms will continue and escalate over time whereas with other conditions they will improve with treatment or wax and wane in severity.

Like with most cancers, the underlying cause of transitional cell carcinoma is unknown. Known carcinogens called renally excreted tryptophan metabolites accumulate in the bladder and are one potential chemical known to cause these types of cancers.

In order for your veterinarian to properly diagnose TCC in your cat, and differentiate it from other urinary conditions, it will be important to provide a thorough medical history. Additionally, you should document any changes in your cat’s urination or litter box habits, and any general tiredness, sickness or eating or sleeping changes that may indicate a systematic spread of the disease.

Your veterinarian will perform a thorough physical examination, paying special attention to the lower abdomen area where the urinary tract is located. They will attempt to manually feel for any masses or disruptions in the typically smooth-feeling of the organs. Your vet will also order a urinalysis and workup of a complete blood profile to check for infection or elevated levels that may indicate cancer has spread throughout your cat.

Your vet will also order a series of x-rays for your cat. The first x-ray will focus specifically on the urinary tract area. This x-ray is called a intravenous pyelography and uses contrast dye to better identify the kidneys, bladder and other organs. While there are many forms of contrast imaging, meaning the injection of dye or materials that will contrast on an ultrasound or x-ray, this is the most popular. Your vet will use these x-rays to determine the presence of any masses and their specific location and size, which will help determine whether surgery is a viable treatment. Finally, your veterinarian will also order x-rays of the rest of your cat, focusing on the thoracic, or chest, x-ray and the abdomen. These will help determine whether the cancer has spread, or metastasized.

Depending on the severity and operability of the tumors and the age and general health of your cat, there are several different treatment options that may prolong the life of a cat affected with transitional cell carcinoma. Currently there is no known cure and most treatments are palliative in nature.

Surgery

If the TCC is in the form of an isolated tumor, surgery to remove the mass may significantly prolong the life of your cat. Given the aggressive nature of this type of cancer, surgery, when possible, is the most recommended course of treatment. Your cat will have to undergo anesthesia and a major surgical procedure where part of the bladder is removed. If the urethra is blocked at the time of surgery, tubes to clear the blockage and assist with your cat’s ability to urinate may be inserted at this time.

Chemotherapy and Radiation

Chemotherapy or a form of radiation therapy, is also an option, either in connection with surgical removal of the tumor, or on its own. In chemotherapy, your cat will be injected with a chemotherapy drug which will work to target and kill the cancer cells. In radiation treatments, specific strengths of radiation are targeted in the area of your cat’s tumor. Radiation and chemotherapy can both cause damage to surrounding tissues and cells. They also can cause additional symptoms such as lethargy, loss of appetite and increased risk of infection or sickness. Certain drugs can be given to help lessen these symptoms.

With current technologies, all treatment of transitional cell carcinoma in cats is considered palliative. This means that treatment is meant to alleviate the physical pain and discomfort of the disease and lengthen the life of your cat. With a well-developed and consistent treatment, your cat’s lifespan may be extended by eight months to a year or more.