Understanding transitional cell carcinoma in canine patients

In a pre-conference interview with dvm360, Craig A Clifford, DVM, MS, DACVIM (Oncology), talked about the most common bladder tumor in canines: transitional cell carcinoma, or urothelial carcinoma. In the interview, Clifford differentiated between superficial and invasive forms of the disease, explaining that the latter is more prevalent in dogs than in humans.

According to Clifford symptoms of transitional cell carcinoma mirror those of a urinary tract infection, often leading to misdiagnosis and delayed treatment. He also talked about the Cadet BRAF test assay and how it works.

Below is a partial transcript. It has been lightly edited for clarity.

Craig A Clifford, DVM, MS, DACVIM (Oncology): So we know that transitional cell carcinoma, or now, as you'll start to see in the literature, we're using a term that is used on the physician-based side, and it's called urothelial carcinoma. It means the same thing, and for the most part, we use the terms together.

We know it's the most common bladder tumor of dogs, and it's actually a model for the disease in people. You know, when I speak to an owner, I describe that the bladder is like a bounty paper roll with many layers to it, and the cardboard layer, the inner lining, is made up of cells called transitional cells. So when they transform and become cancerous, we call it transitional cell carcinoma.

When we get it—people—the most common form we get is called the superficial form. So truly it's only in that cardboard layer. So for us, we can go in and take it out surgically, instill medications in the bladder and destroy it.

The second form, which is less common in people, but is the most common form in dogs is called the invasive form. So by definition, it means it dives down deeper. So it's a very difficult form to remove surgically, unless it's located all the way on the other side of the bladder, what we call the apical area. This tends to occur in the trigone. So in order to remove it completely, you have to reroute three tubes, which is very challenging to do.