Bladder masses in dogs

Bladder masses in dogs are rare. They make up around 1-2% of all tumours identified in dogs. Most bladder masses in dogs are cancerous and life-limiting. Middle-aged, female dogs and certain breeds are most at risk of bladder mass tumours.

Bladder masses in dogs cause problems passing urine. Bladder stones may feel like masses, but they’re not made of tissue. Bladder stones can be removed or dissolved. Bladder tumours are attached to the bladder wall. The first signs are likely to be difficulty peeing or blood in the urine. Bladder tumours are aggressive. With cancer treatment, survival time is up to a year. Prompt identification and treatment offer a better outlook. Always seek help from a vet if you notice anything abnormal when your dog pees.

Overview

What are bladder masses in dogs?

Bladder masses in dogs are swellings inside the bladder. They grow from the bladder lining or develop separately within the urine.

Bladder stones may feel like masses, but they’re not made of tissue. They result from poor diet, genetics or other health issues. Bladder stones can be removed or dissolved.
Bladder tumours are masses growing on or inside the bladder wall. They’re the second most common type of urinary tract tumours in dogs, after kidney lymphoma. Most are cancerous.
Chronic bladder inflammation occasionally results in the thickening of the bladder lining, polyps or granulomas. Polyps and the conditions that cause them are often uncomfortable, but not cancerous.

Bladder tumours in dogs

Transitional cell carcinomas (TCCs) are the most common type of bladder tumour in dogs.
These cancerous masses develop from the bladder lining.
Bladder tumours occasionally develop from the muscle in the bladder wall.
The most common site of TCC is the bladder trigone, where the ureters enter the bladder from the kidneys, and the urethra leaves the bladder.
Symptoms develop due to blockage, inflammation, pain and spread to other organs.
Bladder tumours rapidly spread to other tissues and organs, including lymph nodes, kidneys, liver and lungs.
Diagnosis is often delayed because the symptoms resemble other, more common, bladder problems.
Survival times with treatment are around 6-12 months. This will vary, depending on the stage at diagnosis and response to treatment. Life expectancy without treatment is less than 6 months. Without treatment, quality of life is likely to be poor.

Symptoms

What are the signs of bladder masses in dogs?

It’s often hard to recognise the early signs of bladder masses in dogs. This is because the symptoms resemble those of bladder infections, non-infectious cystitis, blocked bladder or bladder stones.

Early symptoms:

Straining to pee and passing small amounts of urine frequently
Crying or vocalising with pain when urinating
Blood in urine
Bad smell to urine
Getting repeated urinary tract infections that don’t respond to treatment
Becoming quiet and withdrawn

Later symptoms, with invasion and metastasis (spread):

Getting a blocked bladder
Eating less and losing weight
Having difficulty passing poo; narrow, flattened poo shape.
Becoming weaker and lethargic
Developing symptoms of kidney disease
Having a distended or swollen tummy
Collapse, coma and death

Risk

Which dogs are most at risk of bladder masses?

Dogs of all ages, sex or breed can develop a bladder mass. However, certain factors increase your dog’s risk:

Belonging to certain breeds. Scottish Terriers have a genetic (inherited) factor that significantly increases their risk. Other higher-risk breeds include Beagles, Shetland sheepdogs, West Highland terriers, and wire-haired fox terriers
Being female
Having suffered from repeated bouts of cystitis or urolithiasis
Being middle-aged or older
Being overweight
Possibly exposure to certain chemicals, including garden pesticides and drugs

Diagnosis

How can vets diagnose bladder masses in dogs?

Once you report the changes to your vet, the vet will carry out a physical exam. They may be able to feel firm and possibly painful swelling in your dog’s tummy. They will then advise further tests to find out what is causing the swelling:

Urine tests: general urine analysis and checking for things like abnormal cells, crystals or casts
Blood tests
X-Rays: abdomen and chest.
Contrast X-Rays: using a special dye to outline the mass on an X-ray
Cystoscopy: using a special camera to examine the bladder from the inside
FNA and Biopsy: collecting samples of cells or tissue to send to a specialist laboratory for identification.
Other tests may include CT, MRI, exploratory laparotomy.
The CADET Braf test is an advanced genetic test that looks for TCC cancer markers in cells from free-catch urine samples. It also helps with monitoring response to treatment.

Vet treatment

How can vets treat bladder masses in dogs?

Most bladder mass tumours in dogs are aggressive cancers. They can’t be cured. The goal of treatment is to slow down deterioration and make your dog feel as well as possible for as long as possible.

Options include:

Chemotherapy
Partial surgery to reduce the size of a cancerous bladder mass. The location of TCCs makes them impossible to completely remove
Non-steroidal Anti-inflammatory medicines: Piroxicam or meloxicam
Combinations of the above

Home treatment

Caring at home for a dog with a bladder mass

There are no home remedies for bladder masses in dogs.

It’s important to make your dog as comfortable and relaxed as possible at home. This means:

Giving all prescribed medicine at the correct time and dose
Letting them rest when they need and want to
Providing a safe, quiet and comfortable place to sleep
Giving them peace from visitors and other household pets
Encouraging them to drink
Feeding a special prescription diet to provide the best nutrition and help appetite. Examples include Hills Prescription Diet ON-Care, Hills Prescription Diet a/d, Iams Maxi-Calorie.

Always talk to a vet about special diets and caring at home for your dog with bladder cancer.

Despite treatment and the best homecare, bladder cancer will worsen until palliative care can’t keep your dog comfortable any more. When that time comes, euthanasia will be the kindest option.

There is no easy way to face such a heart-wrenching decision. Our Quality of Life Guide may help you to assess how your dog is coping with their illness. Putting them first is the best we can do.

Prevention

How to reduce the risks of bladder masses in dogs

We don’t fully understand what causes bladder mass tumours in dogs. So it’s not possible to completely remove the risk of developing one. But given the link between chronic or recurrent cystitis and bladder tumours, reducing the risk of bladder inflammation may help:

Feeding your dog the best diet for their age, breed and lifestyle
Keeping them slim, with a healthy body condition score
Providing a urinary tract supplement to boost urinary tract health, such as Protexin Cystopro or Cystaid

When to worry