Info... canine bladder cancer

The most common type of bladder cancer found in canines is transitional cell carcinoma (TCC). This is a very aggressive, fast-moving cancer. Since many symptoms mimic that of a common urinary tract infection (UTI), bladder cancer generally isn't diagnosed until it is fairly well advanced. And since UTIs can accompany tumor growth, it wouldn't be unusual to go through a few courses of antibiotic treatment where the dog's symptoms will disappear and then recur after a couple of weeks or months. By the time one suspects it might be more than a garden variety infection, a cancerous or benign growth could be fairly well advanced.

You can read more about TCC, its prognosis, and treatment options on the Purdue University vet school's site and on Rennie's Page.

It might be difficult to think of a three-legged, cancer-affected dog as "lucky" but Jake is definitely a lucky dog. His tumor was not TCC; it was a more uncommon form of cancer — leiomyosarcoma. This is a cancer affecting smooth muscle tissue such as is found in the digestive tract and the genitourinary tract. It is relatively slow spreading and if a tumor can be completely removed, the chances are good that it won't be back.

In order to completely remove the tumor with good margins, 80% of Jake's bladder was removed. Bladder tissue is the most elastic tissue in the entire body, and even if a large portion of the bladder is removed, in many cases it is possible that full capacity will be regained over time as the bladder tissue is able to stretch out again. That's amazing.

Unfortunately, Jake has not regained full capacity, although the fact that he regained as much as he did with only 20% of his bladder left is still pretty amazing to me. So at this point it seems we will have to resign ourselves to the fact that he'll probably have some degree of post-surgical urinary incontinence for the rest of his life.

Over the last couple of months, we have been trying some different drugs to see if they would help. Jake's vets and I are all somewhat reluctant to have a cancer patient use the male or female hormones that are often used to treat incontinence. So the drugs that are being tried are those that "tighten up" smooth muscle tissue. Since these drugs can affect all smooth muscle tissue in the body, including the heart (!!) it was important that Jake was in good cardiac health and that he is not taking any other medications that could interact.

The drug that is working the best so far is phenylpropanolamine (PPA). This drug has a proven track record in helping with canine incontinence, which is actually quite prevalent among older spayed females. When the FDA took the OTC drugs containing PPA off the market due to the potential stroke risk for human females, it caused quite a ripple among those who were using Dexatrim and other diet aids or decongestants not for themselves, but for their female dogs' incontinence.

Although there was a shortage at one point, it doesn't seem to be a problem to get it prescribed for appropriate veterinary uses. But it certainly isn't as economical as it would have been when it was still available OTC for humans.