How Bladder Cancer is Diagnosed in Dogs (First Vet)

More than 50% of dogs diagnosed with bladder cancer have TCC that involves the urethra. A tumor in the urethra can block urine flow, causing the affected pet to strain while attempting to urinate. If urine is unable to pass through, it can eventually lead to damage to the kidney and possibly kidney failure.

• The tumor usually develops in the lower neck of the urinary bladder, which makes surgical removal impossible. This causes a partial or complete obstruction to the flow of urine during urination. The tumor may be felt by a veterinarian through the abdomen wall if it’s already large.
• A digital rectal exam may also reveal tumors in the abdominal lymph nodes if metastasis has occurred. If the tumor has spread to the bones, lameness and/or bone pain can be observed.

After a thorough physical exam, your vet may recommend the following tests to confirm the initial findings:

• Urinalysis
  Sometimes, the urine of dogs with TCC has cancer cells. However, urinalysis is unreliable when it comes to diagnosing bladder cancer because similar cells may appear during urinary tract infections.

• Blood work
  Most dogs with TCC have normal blood work except when kidney function is already affected. But the blood work results can serve as baseline data when evaluating the effect of treatment options.

• Veterinary Bladder Tumor Antigen (VBTA) Test|
  This test checks the urine of dogs for bladder cancer. However, false positives have been recorded in dogs with bladder infections.

• Imaging
  Bladder tumors are rarely seen on abdominal x-rays unless they have spread to the bones. Chest x-rays are useful in determining whether bladder cancer has spread to the lungs.

• A cystogram may be helpful when the veterinarian suspects the spread of the tumor to the dog’s urethra. The procedure uses a special dye to make the tumor visible during x-rays.
• Abdominal ultrasound can help in assessing the tumor size within the urinary bladder and the size of adjacent lymph nodes.
  
  
• Tissue Biopsy
  This is performed as a definitive test to diagnose TCC or other cancer of the urinary bladder. Cells may be collected via a surgical biopsy or a urinary catheter and examined microscopically.

• Cystoscopy can be used in female dogs.
  The procedure involves inserting a camera into the bladder to visualize the tumor. Cystoscopy can also be used for tumor biopsy. (First Vet)

Tumor Staging for Bladder Cancer (First Vet)

Once TCC is confirmed, “tumor staging” will follow to assess the extent of the tumor.

Purpose of Tumor Staging

• Help determine the best treatment regimen that will be followed
• Provide important information about the prognosis
• Establish baseline data regarding the tumor measurements. This can help determine if certain treatments that will be successful.

Tumor staging is achieved with the help of x-rays (radiographs), ultrasound, and CT scans to see if there is metastasis to the lungs, abdomen, lymph nodes, and other organs. These procedures can also evaluate changes in the kidneys as a result of urine flow obstruction. The exact location and the size of the tumor within the bladder can also be determined. (First Vet)