Bladder Cancer in Dogs: Types, Symptoms, and Treatment

Cancer in the urinary tract most often starts with the growth and division of abnormal cells lining the bladder.  

Unfortunately, treatment options for bladder cancer in dogs are limited and the disease is typically not curable.  

A focus on palliative care and symptom management can help keep your dog comfortable while keeping their quality of life sustainable for as long as possible. 

Let’s look at everything you need to know about bladder cancer in dogs—from symptoms to management.  

What Is Bladder Cancer in Dogs?

Bladder cancer in dogs occurs when a cancerous (malignant) tumor develops from the cells lining the bladder.  

As the tumor grows, it can block the flow of your dog’s urine from the kidneys to the bladder or from the bladder to outside the body.  

Bladder cancer in dogs may also spread to the lymph nodes and other areas.  

Bladder cancer is considered a medical emergency. If your pup is showing symptoms, take them to the veterinarian immediately.  

Types of Bladder Cancer in Dogs  

There are two types of bladder cancer in dogs:  

1. Transitional cell carcinoma (TCC). TCC grows from transitional cells that normally line the urinary tract as a protective layer. TCC is aggressive and can spread quickly. 

2. Leiomyosarcomas (LMS). LMS is considered relatively rare, while TCC is far more common.  

Symptoms between the two types of bladder cancer largely overlap, but TCC is associated more with producing blood in the urine (hematuria) while LMS more often causes obstruction of the urethra. 

Symptoms of Bladder Cancer in Dogs

Signs of bladder cancer in dogs include: 

• Urinating often and in small amounts 

• Having accidents indoors 

• Discolored urine 

• Bloody urine 

• Persistent urinary tract infections (UTIs)

• Lameness 

• Persistent licking of the genital area 

Causes of Bladder Cancer in Dogs

Bladder cancer in dogs doesn’t have one exact known cause. It is likely driven by a combination of factors, including: 

• Breed: Any dog can get bladder cancer, but certain breeds appear to be more at-risk than others, possibly due to an underlying genetic predisposition. These include Beagles, Scottish Terriers, Shetland Sheepdogs, West Highland Terriers, and Wire Fox Terriers.  

• Environmental factors: The use of pesticides and insecticides and traditional flea and tick baths has been linked to TCC in dogs. A 2022 study also found a possible link between tap water with high concentrations of trihalomethanes and bladder cancer in dogs. Exposure to secondhand smoke has also been tied to bladder cancer risk. 

• Age: As with nearly all other types of cancer, older dogs are more likely to be diagnosed than younger dogs. 

• Sex: Female dogs are more likely to be diagnosed than male dogs. One suggested reason is that female dogs do not empty the toxins in their bladders as often as males do with scent marking. 

How Veterinarians Diagnose Bladder Cancer in Dogs

Many symptoms of bladder cancer are like those of a urinary tract infection, so your veterinarian will need more invasive tests to make a definite diagnosis. 

Veterinarians diagnose bladder cancer in dogs using a combination of approaches: 

• Blood work: Blood analysis can help check your dog’s overall health and note any abnormalities in organ function, such as the kidneys. 

• Ultrasound: An ultrasound can help visualize masses in the urinary tract. 

• Cystoscopy: A cystoscopy involves a flexible scope that is put into the urethra and bladder while your dog is under anesthesia to view the surrounding tissue and possibly take a biopsy sample. 

• Urine cytology: This can help find abnormal cells in your dog’s urine. 

• Genetic testing: While still in the early stages of application, genetic testing to look for a mutation in the BRAF gene that indicates TCC may signal the presence of cancer in the body. 

Upon diagnosis, your dog’s veterinarian will do tumor staging to figure out whether the cancer has spread, which can involve X-rays,  CT scans, and more ultrasounds. Staging can greatly help the veterinarian figure out your dog’s prognosis.  

You’ll want to let the veterinarian know any changes in behavior or symptoms you’ve seen in your dog, as well as their previous medical history. It’s helpful to provide records before your visit. 

Treatment of Bladder Cancer in Dogs

Treatment options for bladder cancer in dogs depend on the cancer’s nature, size, location, and stage, as well as your pet’s overall health.  

• Surgery: Surgery is not common, because the tumor must be located away from the “neck” of the bladder and the urethra to fully remove it while keeping the bladder sufficiently intact to function post-operation. Smaller tumors far from the neck of the bladder with big enough margins may be options for removal. Laser ablation is sometimes used to destroy part of the tumor instead of doing full surgery. 

• Radiation therapy: Radiation is suggested with caution. It can lead to more complications and permanent damage, since the bladder can move and change shape depending on how much urine is in it. This movement limits the accuracy at which radiation can be applied, potentially hitting nontarget tissues and organs in the body. 

• Chemotherapy: Intravenous (IV) or oral chemotherapy drugs—such as vinblastine, mitoxantrone, or chlorambucil—may be suggested to treat bladder cancer. Your dog may have an upset stomach, vomiting, appetite loss, and lethargy as side effects.  

• Nonsteroidal anti-inflammatory drugs: NSAIDs such as piroxicam are often prescribed for bladder cancer to lower inflammation (swelling), slow tumor growth, and increase your dog’s comfort level. NSAIDs and chemotherapy may be used together. 

• Tube cystostomy: If the tumor is blocking the urethra, stents or a tube may be put in to restore urine flow to outside the body. 

Recovery and Management of Bladder Cancer in Dogs

Bladder cancer in dogs is typically not curable, since it’s often aggressive and has limited treatment options.  

Remaining lifespan depends on factors such as whether the cancer has spread, how aggressive it is, and its size. Suggested treatment options commonly focus on slowing down tumor growth while giving your dog more time and a good quality of life. 

There are many ways you can help ensure your dog’s comfort and manage their symptoms with the support of your dog’s veterinarian: 

• Pill pockets (such as Greenies Pill Pockets Canine Chicken Flavor Natural Dog Treats)  

for helping give oral medications. 

• Pee pads to help your dog with frequent urges to urinate. 

• Dog diapers to manage bladder incontinence (loss of control). 

Prevention of Bladder Cancer in Dogs

There are a few suggested factors related to bladder cancer in dogs.  

Reducing your dog’s exposure to the following may help prevent bladder cancer: 

• Lawns treated with herbicides and pesticides 

• Flea dips and sprays 

• Unfiltered water  

• Secondhand smoke 

In addition, keeping your dog at a healthy weight and prioritizing veterinary appointments can help in preventing bladder cancer or detecting it earlier.