Oral Masses/Ulcers in Dogs and Cats

June 17, 2002 (published) | June 21, 2016 (revised)

What are oral masses?

Oral mass before surgery. Photo by Dr. Jan Bellows

Some dogs and cats develop growths in their mouths. Similar to humans, these growths may be benign or malignant. Once a mass is noticed, analysis must be made to determine the cause of the growth.

What causes oral masses?

Some masses are due to infections in the gums or of the tooth itself. Many are due to tumors. Some breeds are predisposed to certain oral tumors (example: black cocker spaniels are prone to oral melanomas).

What are the signs?

Most pets will not show signs of oral masses until the mass has grown to inhibit chewing or swallowing. In some cases there will be bad breath, excessive drooling and /or a bloody oral discharge.

Oral mass before surgery. Photo by Dr. Jan Bellows

How are oral masses diagnosed?

The entire patient must be evaluated for tumor spread prior to surgery. Usually examination of regional lymph nodes is given and chest x-rays are taken. The veterinarian may take a sample of cells from the mass and examine them under the microscope to give an indication of whether the cause is due to infection or tumor. In most cases the mass will be removed and sent to the laboratory for analysis.

How are oral masses treated?

Pets that have non-malignant tumors can usually be cured by surgical removal or radiation therapy. Malignant tumors usually need more aggressive surgery and/or radiation and chemotherapy to decrease tumor spread.

What is the prognosis for oral masses?

Post-surgical photo of the mouth above. Photo by Dr. Jan Bellows

The prognosis is directly related to the type of mass. With treatment, benign tumors usually result in a normal life span. Those animals affected with aggressive malignant tumors may live only weeks to months after diagnosis with or without treatment.

How are oral ulcers treated?

Therapy of oral ulcers depends on the cause. If due to periodontal disease, teeth cleaning, polishing, and strict home care may affect a cure. Many times the teeth adjacent to the ulcer will need to be extracted in order for ulcer to heal. Oral rinses containing zinc are helpful in the healing process.

What is the prognosis for oral ulcers?

Generally the prognosis is excellent for oral ulcers once the underlying cause is diagnosed and controlled.

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