Snow Leopard

Snow Leopard
Snow Leopard cub (7 mos old) - Cape May County Zoo

Thursday, January 13, 2011

Oral Tumors in Pets

Unfortunately sometimes bad breath signals something more serious than dental disease. There are several types of growths that can occur - both benign and malignant.
It has been reported that 6% of all cancers in dogs are in the oral cavity, while it’s 4% for cats. 
One quick note before I explain a bit further: In general, cats usually have a higher incidence of malignancy than dogs (regardless of where the tumor or mass is located). Because of this, I am always more aggressively pushing the cat owners to intervene early! 
There are some benign growths but even some of these can be very locally invasive and difficult to remove completely. The most common of these is an epulis, which is basically like an “overgrowth” of the gum next to a tooth. In some breeds, such as Boxers, there can be quite a few of these. There are some types that are more aggressive and need further treatment than simple surgical removal.  There are cases where either part of the bone/jaw needs to be removed or radiation therapy is recommended. 
There are 2 ways to classify the malignant, or cancerous, tumors: those that have a high rate of spread (metastasis) and those that don’t tend to spread to other parts of the body (such as the lungs or liver, etc). 

<----Note how as this grows, it's totally distorting things - the lower k9 tooth and incisors are going in different directions than they are supposed to!

Fibrosarcomas and squamous cell carcinomas are the types that have a low rate of spread. This doesn’t mean that are easy to remove. Again, sometimes radical surgery, such as a hemimandibulectomy (removing half of the lower jaw, for example) is needed to get clean margins (making sure no tumor cells are left on the edge of the tissue being removed). 
Melanomas (yes, like those that occur on skin in humans) are not only malignant but can  spread to the lungs. They generally have a black appearance but some lack pigment (amelanotic) and are pink in color. Cockers and German Shepherds seem to have a higher incidence of these.  Osteosarcomas (bone tumors) can also occur in the jaw bones of the mouth. 
The bottom line is that no one can tell just by looking at the growth what it is -a biopsy is needed.  Dental radiography is also often used to assess to what extent the jaw bones are involved. When the jaw bones are involved, the bone is destroyed, becomes weak and can fracture with not a lot of effort - the simple acting of chewing could do it!

This could appear to be simply irritation/inflammation BUT it turned out to be  Squamous Cell Carcinoma in a 5yr old Golden Retriever.

 At the time of the procedure, your vet may or may not remove the whole thing or at least remove some of it (debulk) it - especially if it’s causing a problem with the animal eating. However, they may simply want to get a diagnosis via a biopsy so that they can advise you further on treatment - that may be partial removal (to buy time/quality of life), referral to a board- certified veterinary surgeon for more extensive surgery and/or an oncologist for radiation/chemotherapy or even euthanasia (especially if there is already spread to the lungs and/or the animal has little to no quality of life). 
Below are some sites that can give further info and photos (and are from VETERINARIANS, including boarded surgeons, etc) - not groomers, breeders, your neighbor...

1 comment:

  1. I just saw a growth today in a cat - originating from the upper lip. The owner thought it might be a problem with the upper canine tooth - a common misconception with tumors in this area. Given that it is an older cat, it is LIKELY this is malignant. However, it it small enough at this time to be surgically removed, hopefully with good margins and not too much distortion to the upper lip/facial appearance.