A common tumor in the mouth is the epulis, seen most often in Boxers and Bulldogs. These benign tumors grow from the periodontal membrane in response to gum inflammation. They appear as growths on a flap of tissue. There are often multiple growths. Rarely, an epulis becomes malignant.
Gingival hyperplasia is a condition in which the gums grow up alongside or over the teeth. A familial inheritance has been identified in Boxers, and is suspected in Great Danes, Collies, Doberman Pinschers, and Dalmatians. The enlarged gums can interfere with eating and are easily traumatized. They also predispose the dog to periodontal disease. If any of these occur, the enlarged gums should be surgically removed.
Malignant tumors in the mouth are rare. In order of frequency, they include melanoma, squamous cell carcinoma, and fibrosarcoma. These tumors tend to occur in older dogs. Biopsy is required to make an exact diagnosis. Dogs with oral tumors may drool, have trouble eating, and/or have a very foul odor to their breath. The drool may be bloody.
Treatment: Early, aggressive treatment of mouth tumors, with wide local excision and/or radiation therapy, offers the best chance for a cure. Surgery may involve removing part of the upper or lower jaw. In many cases the tumor is already too far advanced for treatment. The prognosis is best for squamous cell carcinomas. Fifty percent of treated dogs survive a year or longer.