Should You Remove Your Dog’s Epulis? Here's What You Need to Know
When your dog develops a mass in its mouth, such as an epulis, it’s natural to feel concerned. One specific type of epulis, now more accurately referred to as canine acanthomatous ameloblastoma (CAA), is a common yet locally invasive tumor of the gingiva, previously lumped together with other benign oral masses. Understanding this condition is critical for ensuring your pet receives the best possible care.
What Is Canine Acanthomatous Ameloblastoma (CAA)?
CAA is a benign but locally invasive tumor arising from remnants of odontogenic epithelium—essentially tissues involved in tooth development. It most commonly appears in middle-aged dogs, particularly in breeds like:
- Golden Retrievers
- Cocker Spaniels
- Akitas
- Shetland Sheepdogs
Though benign—meaning it doesn’t metastasize (spread to other organs)—this tumor can be aggressive in the way it invades surrounding tissues, particularly bone.
Clinical Signs to Watch
A dog with CAA may show signs such as:
- A firm, irregular growth on the gums
- Ulceration or necrosis of the mass
- Tooth loosening or displacement
- Facial swelling
- Oral bleeding and drooling
- Difficulty eating or chewing
- Foul breath (halitosis)
Some tumors are only found during routine dental exams, as early signs can be subtle.
Diagnosing the Tumor
Diagnosis involves multiple steps, including:
- Clinical evaluation
- Histopathological biopsy—tissue samples are examined microscopically
- Dental X-rays or CT scans—to evaluate bone involvement
- Cytologic and immunohistochemical studies—to identify specific tumor cell characteristics
A key histologic feature of CAA is the presence of squamous epithelial cells forming islands and sheets, often surrounded by palisading cells. These tumors show distinct infiltration into nearby bone structures.
Why Removal Is Typically Recommended
Surgical removal is the gold standard of treatment for CAA. Despite its benign classification, the tumor’s invasive nature means that incomplete removal can lead to recurrence rates of up to 91%. A complete excision—often involving en bloc resection with 1–2 cm margins of healthy tissue—is deemed curative.
For smaller tumors (<2 cm) with minimal bone invasion, a rim excision may be sufficient. Most dogs adapt well even after partial jaw removal and regain normal function and quality of life.
Alternative Treatments
When surgery is not possible due to tumor location or owner preference, alternative options include:
- Radiation therapy—effective in most cases but carries risks like osteoradionecrosis and the potential for secondary tumors. Around 80% of dogs remain tumor-free for at least 3 years post-treatment.
- Intralesional chemotherapy—involving agents like bleomycin, though it is less commonly used due to local adverse effects such as wound formation and tissue irritation.
Prognosis After Treatment
The outlook for dogs treated with complete excision is excellent. Studies report a 1-year survival rate between 97–100% for those receiving wide-margin surgery. After successful treatment, most dogs resume normal activities and enjoy a high quality of life.
Monitoring and Follow-Up
Regular veterinary check-ups and possibly imaging studies are recommended to ensure the tumor does not recur. Since metastasis is not a typical concern with CAA, follow-up primarily focuses on the site of surgery.
Scientific Advances
CAA is now known to harbor mutations in genes such as HRAS (especially the p.Q61R variant) and sometimes BRAF. Over 60% of tumors show these mutations, which mirror those seen in human ameloblastomas. These similarities position CAA as a valuable model for studying targeted cancer therapies and advancing both veterinary and human oncology.
Conclusion
If your dog has been diagnosed with an oral growth identified as epulis or more specifically as canine acanthomatous ameloblastoma, surgical removal is highly recommended. Though benign, its invasive potential can lead to serious complications if not adequately addressed. With early detection, accurate diagnosis, and complete excision, your dog has an excellent chance at a full recovery and long, healthy life.





