Transitional cell carcinoma (TCC) is the most common dog bladder cancer. Let’s go over the most important things to know about this cancer.
Transitional What? TCC Explained
Your dog’s urinary tract is lined with some really cool and unique cells called transitional cells. Transitional cells are called transitional because they change depending upon what’s happening in the area.
They can stretch and then bounce back to their normal form. This is is why your dog’s bladder can expand to hold urine! Transitional cells expand like the walls of a balloon to accommodate urine, and then bounce back to their small form when the urine empties.
Transitional cell carcinoma is when these cells become cancerous.
Transitional cells are in the bladder, of course, but they also line the ureters and urethra.
Ureters are the tubes that bring urine from your dog’s kidneys to his bladder. The urethra is the tube that takes urine from the bladder outside of the body.
All of these tubes connect with the bladder in a region known as the trigone.
While TCC can arise anywhere, it’s most commonly found in the trigone area, which is one of the reasons it’s hard to treat.
Any dog can get transitional cell carcinoma, but the are some genetic and environmental risk factors. Female dogs are more likely to get it than males, and obesity increases risk as well.
Breeds who are at high risk for developing TCC include:
- Scottish Terriers
- Shetland Sheepdogs
- West Highland White Terriers
- Airedale Terriers
- Wirehaired Fox Terriers
While Scotties are the most commonly affected dogs, there is some good news! A study found that feeding vegetables at least three times a week decreased the rate of TCC in Scottish Terriers. Broccoli for everyone!
Environmental factors that increase the risk for TCC include:
- Exposure to insecticides
- Exposure to herbicides
- Topical flea and tick medications
- Treatment with the chemotherapy drug cyclophosphamide
Remember, there are many causes of cancer, and some of them we can’t avoid. No one can live in a bubble.
But these are the KNOWN factors that may increase risk in dogs.
Symptoms of Transitional Cell Carcinoma
Unfortunately, many of the symptoms of TCC look very similar to a urinary tract infection. Symptoms include:
- Frequent urination
- Urinating small amounts
- Straining to urinate
- Blood in the urine
- Secondary urinary tract infection
- Symptoms recur after treating for UTI
- Inability to urinate (obstruction)
These are all symptoms of urinary tract infections, too, which are much more common than TCC.
Often, dogs don’t get diagnosed with TCC until after they have been treated for UTI’s and the symptoms don’t go away.
Bladder cancer is often painful, and many dogs have a constant urge to urinate. This can be frustrating for dogs and humans!
NOTE: If your dog is unable to urinate at all, this is an emergency. The buildup of waste products inside the body can be fatal within a matter of days. If you’re reading this because you notice your dog is not able to urinate, take her in for an emergency vet visit right now.
As mentioned above, dogs with transitional cell carcinoma frequently come into the vet for a suspected UTI.
Once they are treated, owners notice they don’t improve on medications … or immediately start showing signs again once they finish treatment.
If this happens, or if your dog is a high-risk breed for TCC, your vet will recommend additional diagnostic tests.
The first step is almost always a urinalysis. This is when your vet examines your dog’s urine under a microscope to look for abnormal cells, bacteria, and crystals. The urine will also be tested for its pH and the presence of proteins or glucose.
Bladder Tumor Antigen Test
This is a special test that looks for tumor proteins in your dog’s urine. There are very few false negatives – so if your dog tests negative, she almost certainly does not have bladder cancer!
There is a risk of false positives, however. This is because the protein in the urine due to a UTI or kidney failure can also trigger the test. So if your dog tests positive, she will need additional testing to confirm the diagnosis.
CADET BRAF Test
This is another special urine test that looks for a mutation that occurs in most TCC tumors. For this test, there are very few false positives – so if your dog is positive, she very likely does have TCC.
There can be some false negatives with this test because not all TCC tumors have the BRAF mutation.
A cystocentesis or “cysto” is when your vet or a technician uses a needle and syringe to take a sterile urine sample directly from your dog’s bladder. Your dog will be placed on her back or side, and a long needle inserted into the bladder.
While this sounds terrifying, it is actually really quick and dogs tolerate it very well!
Your vet will do a cysto if she wants to confirm the presence of a UTI or wants to send out urine for a culture and sensitivity test to identify the exact bacteria causing the problem and the best antibiotic to kill it.
If your dog might have TCC, however, your vet may not want to do a cysto. Some studies have shown that there is a risk of “seeding” the tumor and spreading cancer cells along the path that the needle takes. Other studies have not shown this to be the case. Here’s a good article from Dr. Dressler about this nuanced subject.
Bloodwork for TCC
Blood tests won’t tell if your dog has transitional cell carcinoma or not.
But they will give your vet lots of info about your dog’s overall health.
Your vet will be especially interested in your dog’s kidney health – if her kidney values are out of whack, she may be in kidney failure.
Kidney failure alongside TCC complicates things, and may change your thinking about treatment — so it’s good to know about it.
An X-ray is a quick way to get a look at your dog’s bladder. For the best results, her bladder should be pretty full at the time of the x-ray. This lets your vet see as much of the bladder wall and the space inside the bladder as possible.
Tumors are not always visible on X-ray, but bladder stones will be if your dog has them.
An ultrasound is a better way for the veterinarian to look at the bladder wall because it shows soft tissue better than x-rays do. Again, the bladder should be full to give the best view.
Ultrasounds are also useful to check the abdomen for signs of metastasis, or cancer spread.
In some cases, your vet may recommend getting a biopsy of the tumor once it has been found.
This can be done via cystoscopy or passing a tiny fiberoptic cable with a camera and little grippers up the urethra into the bladder, or it can be done surgically. Both of these procedures will require anesthesia.
Staging the Cancer
If your dog is diagnosed with TCC, your vet will also “stage” the cancer. This tells you how severe your dog’s condition is at this time.
Stage T1 is a superficial tumor.
Stage T2 is a tumor within the bladder wall.
And Stage T3 is a tumor that is invading surrounding organs and tissues.
As with most cancers, lower stages come with a better prognosis. The average survival time for Stage T1 with treatment is 6-7 months.
Treatment Options for Dog Bladder Cancer
The “standard of care” treatment for dogs with transitional cell carcinoma is chemotherapy combined with a nonsteroidal anti-inflammatory drug (NSAID).
Non-steroidal anti-inflammatory drugs are a mainstay of transitional cell carcinoma treatment.
Why? Because they do two things: make the dog feel better and sometimes shrink the tumors.
Piroxicam, a human NSAID, is the best-known option for dogs with TCC, but other NSAIDs like deracoxib (Deramaxx) or meloxicam (Metacam) work too.
An NSAID provides palliative control even by itself, which means that it just makes your dog feel better even when it doesn’t fight the cancer.
NSAIDs also work alongside chemo, surgery, or radiation, so using one doesn’t mean you can’t use those other treatments.
If your veterinarian wants to start your dog on an NSAID immediately, those are a lot of good reasons to do it!
According to Dr. Susan Ettinger, DVM, DACVIM, in the Dog Cancer Survival Guide, “Chemotherapy treatments can prevent recurrence, prevent or delay metastasis, and extend survival times.” Chemo can be used alone, or in addition to surgery and/or NSAIDs.
Chemo drugs commonly used for TCC include:
- Mitoxantrone – this along with an NSAID is the gold standard for TCC, with median survival times of 12-14 months!
- Cisplatin – should not be given with an NSAID due to the increased risk of kidney damage
Most of these drugs are given via injection, so treatments do require a vet visit.
Chlorambucil, on the other hand, is an oral medication that can be given at home.
Surgery may play a role in bladder cancer treatment, but it can’t do the job alone.
The bladder is a very unique and important organ, so the surgeon may not be able to remove the entire tumor without permanently damaging your dog’s urinary tract. If the tumor is located at the trigone, or the spot where all of the different tubes come into the bladder, surgery may not be possible at all.
What surgery CAN do is debulk the tumor, making it smaller. A smaller tumor means less discomfort for your dog, plus less risk of obstruction. And it can also help other treatment measures work better.
If your dog has a urinary obstruction, surgery can also be used to place tubes that allow urine to bypass the blocked area. These procedures can have a lot of complications, including urinary incontinence, so it is important to discuss all of the potential outcomes for your dog’s case before jumping in.
Radiation therapy isn’t commonly used for bladder cancer because it can potentially damage the bladder wall and prevent it from working properly. It might be an option for some cases, though, depending upon the location of the tumor. Your oncologist will let you know if it’s an option.
Diet and Supplements
As with all cancers, implementing a low-carb diet rich in vegetables can help to support your dog’s immune system.
There are also lots of supplements that can be beneficial in your dog’s fight against cancer. Some options for TCC include:
- Cordyceps mushroom to protect the liver and kidneys during chemo
- Coenzyme Q10 to protect the heart if treating with doxorubicin
- Apocaps CX to support natural cell death
- Fish or krill oil to combat inflammation
- Modified citrus pectin to help slow metastasis
There are plenty of studies that show that lifestyle modifications to reduce stress and increase happiness are important. Dr. Dressler recommends things like ensuring a dark sleeping space, fresh air and exercise, and play sessions. Training challenges can help keep a dog interested and motivated, too.
Bottom Line on TCC in Dogs
There is no cure for dog bladder cancer, but treatment can extend survival time and dramatically improve quality of life.
Unfortunately, bladder cancer hurts. If you’ve ever had a UTI, or even just really had to pee, you understand how uncomfortable it could be for your dog.
That’s why no matter what, whether your dog is a candidate for surgery or not, you can always give an NSAID to relieve discomfort. Chemotherapy is also often part of the treatment plan.
Additional things that you can do at home include giving supplements to support your dog’s immune system and feeding a low-carb diet.
Paws and Wags,
Further Reading and Resources
Here’s a good podcast episode where a listener asks a question about TCC:
Kate Basedow grew up training and showing dogs, and her passion for canines has affected all parts of her life. She earned a BA in English from Cornell University and an AAS in Veterinary Science from SUNY Delhi, and is a licensed veterinary technician in the state of New York. Her writing on dog-related topics has earned numerous awards from the Dog Writers’ Association of America and the Alliance of Purebred Dog Writers. Kate currently serves and adores two Belgian Tervuren and a Pembroke Welsh Corgi.