Oral cancer is one cancer that grows and then spreads quickly and is often very hard to treat. In fact, as far as cancer goes, it is one of the most difficult to treat. Tumours found in the mouth are quite common and can be either cancerous (malignant) or non-cancerous (benign). Mouth cancer is actually the fourth-most common cancer in dogs.
Malignant tumours typically spread rapidly through the body and seem to be rooted deep into the tissue of the mouth. Benign tumours can usually be removed through surgery and don’t often spread.
Oral cancer can happen to any dog but seems to be more common in large breeds with dark pigmented skin in the mouth. The cancer doesn’t usually develop in very young dogs.
The location of the masses or tumours is usually around the upper teeth or on the roof of the mouth. These masses need to be caught early in order to treat because they tend to grow extremely fast and then begin spreading to other areas of the body.
Oral cancer doesn’t have any definitive causes. Environmental factors may be involved, such as exposure to carcinogens, toxins, pesticides, or other chemicals. Genetics may also be involved.
There is no known way to prevent oral cancer; however, staying on top of your dog’s oral health will ensure that you find any symptoms early on should they pop up. If you decide to do a dental cleaning the veterinarian will examine the dog’s mouth at this time. Even if you do the dental cleaning on your own at home, you can still examine your dog’s mouth and look for anything unusual.
There are a number of symptoms to watch for when it comes to oral cancer. They include:
- lesions and sores in mouth area;
- bad breath;
- lumps or masses in mouth area;
- difficulty swallowing and/or chewing;
- bleeding from the mouth;
- excessive drooling;
- decreased eating habits;
- facial swelling;
- weight loss;
- chronic cough;
- loose teeth; and
- swollen glands in the neck.
Dogs at Risk
Oral cancer can affect any dog; however; there are certain breeds with a higher risk. Those with dark pigment/colour around the mouth area are more susceptible to oral cancer, such as black Cocker Spaniels, German Shepherds, Chows, and Scotties. Some believe environmental factors, meaning pollution, also plays a role. In most cases dogs affected by oral cancer are six to 10 years of age. Gender does not affect whether a dog will get oral cancer.
Testing and Diagnosis
An oral exam will need to be conducted when a dog is suspected of having oral cancer. The veterinarian will be looking for any masses inside the dog’s mouth, swollen gums, bleeding, or broken teeth. If a tumour is a found, a biopsy will need to be done in order to diagnosis if the mass is pre-cancerous, cancerous, or benign. Likely, the veterinarian will also check the dog’s lymph nodes to see if they are swollen. A complete physical examination including blood work will need to be done.
Further testing may be required, which could include a CT scan of the jaw area and/or a chest x-ray. The purpose of these tests is to determine if the tumour has metastasized to other areas such as the lungs, the head, and the bone and tissue of the mouth.
Treatment and Prognosis
Oral cancer can be a tricky one to treat and early detection plays a large role in what treatment plan will be given. If the tumour has spread to other areas, surgery isn’t usually going to be the answer. However, if the tumour is found before it spreads it can be removed during surgery. Likely more than just the tumour will need to be removed and tissue and bone around it will also be taken out. In extreme cases, the dog may need part of its jaw taken out. Although it sounds like a scary operation, dogs often recover well with just a partial jaw.
Another option may be chemotherapy that is directly injected into the tumour. Radiation treatment isn’t used for oral cancer.
It should be noted that in the case of malignant tumours, metastasis often occurs before the cancer is detected. As well, tumours have a large change of recurring.
For dogs that had a malignant tumour removed, it is often recommended that a chest x-ray be performed every three months in order to catch anything that might further develop.
The prognosis for the dog depends on whether the tumour was benign or malignant and if a successful surgical removal of the mass was possible.