Bladder cancer in dogs: causes, symptoms & treatment

Bladder cancer in dogs is a serious but relatively uncommon condition, accounting for about one percent of all canine cancers. The most frequent type is transitional cell carcinoma (TCC), which starts in the cells lining the bladder and often grows insidiously without early clear signs. This cancer usually develops near where the kidney meets the bladder, affecting urinary function as it progresses.

This article offers a comprehensive look at bladder cancer in dogs, including risk factors, signs to watch out for, diagnosis, treatment options, prognosis, and important advice on responsible veterinary care.

More about bladder cancer in dogs: transitional cell carcinoma

TCC accounts for up to 95% of bladder cancer cases in dogs. It originates from the transitional epithelium lining the bladder and tends to invade the bladder wall and surrounding tissues. Unfortunately, this cancer is often diagnosed late because early symptoms are subtle or mistaken for urinary infections.

TCC may also spread (metastasise) to nearby lymph nodes, lungs, liver, and in males sometimes the prostate. Its invasive nature can lead to urinary obstructions causing additional health complications.

Causes and risk factors for bladder cancer in dogs

The exact causes of bladder cancer are not yet fully understood. However, veterinary research suggests a combination of genetic and environmental factors contribute:

• Breed predisposition: Dogs like Scottish Terriers puppies and Beagle puppies are more at risk, suggesting heredity may play a role.
• Age and sex: It typically affects dogs over 10 years old and is more common in females (bitches).
• Environmental chemicals: Exposure to pesticides, insecticides (especially those used in livestock), and petrochemicals might increase risk.
• Obesity: Excess weight is linked to higher cancer risk in dogs.
• Chronic urinary infections: Recurrent bladder infections may cause irritation that triggers cancer development.

Symptoms of bladder cancer in dogs: early warning signs

Because bladder cancer often progresses slowly, symptoms may only become noticeable in advanced stages. Vigilance is key to spotting problems early.

Common signs to watch for include:

• Signs of pain or difficulty while urinating
• Frequent urination but passing only small amounts
• Straining to urinate or inability to urinate
• Blood in the urine (hematuria)
• Repeated or hard-to-clear urinary tract infections
• Slightly elevated or recurring fever
• Soft, chronic cough or difficulty breathing during exercise (if cancer spreads)
• Behavioural changes such as lethargy, loss of appetite, or reluctance to play

If you notice any of these signs, especially in older dogs or prone breeds, contact your vet promptly. Early vet intervention improves treatment success and quality of life.

Diagnosis: how vets confirm bladder cancer

Your vet will start with a physical examination and a detailed history of symptoms. They will often recommend:

• Urine tests to look for blood, infection, and cancer cells
• Blood tests to assess overall health and organ function
• X-rays and ultrasound to visualise the bladder and surrounding tissues, tumour size, and possible spread
• Specialised tests like the CADET BRAF test may be used to detect genetic mutations associated with bladder cancer in high-risk breeds

Sometimes a biopsy is performed to confirm the cancer type and guide treatment.

Treatment options for bladder cancer in dogs

While there is currently no cure for canine bladder cancer, treatments aim to control tumour growth, relieve symptoms, and improve your dog’s life quality.

• Surgery: Removing the tumour completely is ideal when feasible, offering the best chance of extended survival.
• Chemotherapy: Often combined with surgery or used alone to shrink tumours and slow progression, though chemo alone is rarely curative.
• Radiation therapy: Advanced options like stereotactic radiation therapy may be considered in some cases.
• Supportive care: Managing urinary infections, pain relief, and nutritional support is vital throughout treatment.

Prognosis and outlook for dogs with bladder cancer

Prognosis varies depending on tumour stage, treatment success, and general health. Unfortunately, many dogs are diagnosed when the cancer is already advanced.

Survival rates after treatment hover around 50%, with surgery generally offering the best outcomes. Chemotherapy improves control but rarely provides a cure. Early detection and aggressive treatment improve chances.

Decisions about treatment intensity or euthanasia should centre on your dog’s comfort and quality of life, in close consultation with your vet.

Supporting your dog: responsible ownership guidance

If you own a breed at risk, regular vet check-ups are crucial, especially as your dog ages. Avoiding exposure to potentially harmful chemicals and maintaining a healthy weight can also help reduce cancer risks.

Always ensure prompt attention to unusual urinary symptoms and seek veterinary advice early. This proactive approach supports better outcomes and a cared-for companion.