Even though its incidence in dogs is somewhat rare, bladder cancer can show up in our canine friends. About 1% to 2% of all cancer cases in dogs affect the bladder.
In today’s article, we’re looking at the symptoms of bladder cancer in dogs, its diagnosis, treatment, and prognosis, and whether some breeds are more predisposed to developing it.
What type of cancer of the bladder can dogs develop?
While there are several different kinds of bladder cancers (leiomyosarcomas and fibrosarcomas are just two examples) that dogs can get, by far the most common one is transitional cell carcinoma (abbreviated as TCC).
Carcinoma, in general, and transitional cell carcinoma, in particular, is one of the most aggressive types of cancers that people and pets can develop.
For this reason, by the time the dog ends up at the veterinary hospital due to urinary symptoms, he or she might have already developed metastases in other nearby organs. The worst thing about TCC is that it can easily spread through the local lymph nodes, and from there, it can basically go to any other major organ (the liver, the lungs, and others).
Also, since the bladder is a part of the urinary tract, the most common locations to which this type of cancer metastasizes are the urethra, the prostate, the ureters, as well as the kidneys.
What causes bladder cancer in dogs?
The exact cause of cancer, in general, and of TCC, in particular, remain unknown. There is a genetic predisposition, so dogs can develop the neoplasm since they are hereditarily more likely to do so, but there are also oncogenic viruses that they can get from their living environment or other animals.
The incidence of TCC in some dog breeds is higher than in others. Here are some examples:
- Shetland Sheepdog
- West Highland White Terrier
- Scottish Terrier
Cancer can also be caused by environmental factors such as pesticides and weed killers, but also some additives and preservatives that common pet food varieties now contain (especially artificial colors).
Symptoms of canine bladder cancer
The clinical signs that bladder cancer can cause in our friends are somewhat similar to those of regular urinary tract infections. For this reason, some pet owners might try to treat it at home.
While it is true that bladder cancer often evolves alongside a bladder infection (mostly because the mucous membrane is affected so the bacteria in the urine can penetrate it with ease and cause infection and inflammation), the difference between the two is that the first causes persistent symptoms.
Some of the typical symptoms of bladder cancer are the following:
- Straining to urinate
- Painful urination
- Blood in the urine
Diagnosis and treatment
Since the symptoms of this disease are so similar to those of urinary tract infections, the veterinarian will recommend a number of tests once you get to the animal hospital.
These can range from typical blood tests such as biochemistry and a complete blood cell count, but they can also involve imaging techniques such as an ultrasound, contrast radiography, and others.
Urine tests should also be performed just to discover what microorganism has led to the infection (since the dog usually develops one, too). A bacterial culture and an antibiogram will lead to a clear diagnosis in this sense, so the veterinarian will administer or prescribe the correct antibiotic.
Once the tumor has been located, additional tests (such as biopsy) are required in order to tell just what type of cancer the dog has. This is done to know the stage it has reached and its malignancy potential — otherwise, the veterinarian and the pet owner cannot opt for the correct treatment.
The therapy can be surgery for the removal of the tumor, chemotherapy, or radiation therapy. The right one can only be selected depending on the location of the neoplasm, its type, and whether it has already spread to other organs — in which case the surgery might be useless.
Given that the incidence of TCC in dogs with blood cancer is relatively high, the prognosis is usually poor. Moreover, even if the surgery is successful, it takes a lot of time for the bladder to recover as the urine is acidic, so the sutures in the bladder wall basically represent entryways for bacteria.
As for whether you should choose to have your dog treated or not, it is entirely up to you and what the veterinarian recommends. Without treatment, some dogs can live for 4 months, but even when they are treated, they can live for just 6 to 12 months.
A combination of surgery and chemotherapy is often used in treating bladder cancer, and depending on the type of neoplasm that the dog has developed, the life expectancy could be higher — 1.5 to 2 years.
Can you prevent bladder cancer in dogs?
Not exactly. If your dog is genetically predisposed to the disease, the best thing you can do is to take him or her to the vet on a regular basis, every 4-6 months, to have a general examination and at least blood and urine tests done.
Even if your dog isn’t likely to develop it, you should still consider a check-up every year until the age of 6 and biannual check-ups after the age of 7.
Unfortunately, you can’t entirely eliminate all of the other factors that can lead to bladder cancer. You can, however, feed your dog the best and cleanest diet you can afford — and you can even make homemade dog food at home if you don’t want any additives or preservatives in it.
Try to protect your dog against insecticides, weed killers, and pesticides, as well as other potentially carcinogenic substances such as bleach or ammonia.