Palatal Ulceration

Meet Finn, a 7 year old Rat Terrier. He presented to our hospital for evaluation of an oral malignant tumor, suspected to be a carcinoma. The swelling had been present for 3-4 weeks, developed relatively quickly, was ulcerated across the palate, and had not responded much to two different types of antibiotics. Finn had a great deal of pain around his mouth and was not eating well. His family veterinarian had biopsied several areas within the lesion which were read as chronic inflammation with suggestions of a malignancy, possible carcinoma. He also had swelling adjacent to the right mandibular 1st molar tooth.

In general, when there is swelling of the jaws of a dog/cat, there are three most likely causes: an abscessed tooth, a cyst, or a tumor. In rare instances the swelling may be sue to several other “unusual” causes. With abscesses, there is usually an underlying source of infection, such as, an infected tooth and these respond to antibiotic but recur when off of antibiotics. Most cysts occur around an uninterrupted tooth and do not respond to antibiotics. These are easily diagnosed with dental x-rays and biopsy.  Tumors usually don’t respond to antibiotic and may show generalized bone loss in an area if they are an invasive malignancy.  Most oral malignancies occur in one area and not multiple areas.  In this case, swelling was noted at the upper left jaw and the soft tissue lateral to the right and left lower 1st molar teeth. It did NOT appear this was the usual case of jaw swelling.

In this case, Dr. Michael Peak at The Pet Dentist at Tampa Bay obtained dental x-rays which did not reveal a cyst but did reveal generalized bone loss. We were concerned about an oral malignancy, however, most malignancies don’t occur in multiple areas, so we decided to take several biopsies from the left upper jaw swelling as well as the lower jaw swellings. The results came back as chronic inflammation, no indication of malignant cells, very suspicious of a sterile granuloma. This is basically an immune response to an unknown cause.

We started immune suppressive medication (cyclosporin) and in 6 weeks the swelling in all three areas had resolved and the palatal ulceration was healing well. Finn was acting much better and was eating better and we plan to continue the medications and eventually slowly taper them off.