Canine Acanthomatous Epulis

Last Modified: May 21, 2006

Dear OncoLink "Ask The Experts,"

My 13-year-old Dalmatian, Pepper, has been recently diagnosed with having an acanthomatous epulis on the front lower-jaw gum line. It was removed a few weeks ago and sent for biopsy with the above results. It has been about 2 weeks since its removal, and it has regrown rather rapidly, now as big -- or bigger than -- it was originally and covering some of his front teeth. I have been told that his only options are to have part of his lower jaw removed or radiation. The vet prefers the first option, but will not do it himself and has referred me to someone else who agrees with the options. I was wondering if there are any other options available? I have been searching the Internet and have found an article about a study where the drug "bleomycin" was injected intralesionally in dogs with these tumors, which then disappeared within weeks. Is this a commercialized, cost-effective option for dogs?

Lili Duda, VMD, Section Editor of the OncoLink Veterinary Oncology Menu, responds:

Acanthomatous epulis is a tumor arising from the periodontal ligament--the structure that holds the tooth in the jawbone. These tumors are benign, in that they do not metastasize (spread) elsewhere in the body, but they are very locally invasive and can grow quite large very quickly. Standard treatment options are surgery or radiation therapy. Surgery that removes the entire piece of affected jawbone with adequate surgical margins is curative.

Radiation therapy can offer local control in about 90% of cases. There are also some conflicting reports in the literature that radiation therapy can occasionally result in the development of a more aggressive tumor at the treated site.

Intralesional chemotherapy--in particular bleomycin--has been reported to have some effectiveness in a single publication of a small series of dogs. This treatment involves weekly injections of chemotherapy into the tumor (with the patient under anesthesia), until either tumor regression occurs or until infection/inflammation precludes further intralesional treatments. It remains to be seen if this treatment option is truly effective. Our limited experience at VHUP is that tumors of the jaw are difficult to inject, and that even distribution of the chemotherapy is difficult to achieve.