Acanthomatous ameloblastomas are a type of oral tumor commonly found in dogs. These growths originate from the cells involved in tooth development, affecting the soft tissues and sometimes the bone structures of the mouth. While they do not spread to other parts of the body, their presence can still lead to significant local issues within the oral cavity. Understanding these tumors is an important step for pet owners.
Understanding Acanthomatous Ameloblastomas
Acanthomatous ameloblastomas, also known as canine acanthomatous ameloblastoma (CAA), are considered benign odontogenic tumors, meaning they arise from the tissue that forms teeth. These tumors are locally aggressive, causing extensive destruction to surrounding tissues like the jawbone and teeth, though they do not spread to distant organs. They are the fourth most common oral tumor in dogs.
These tumors are frequently found in the jawbones, particularly the mandible (lower jaw) and sometimes the maxilla (upper jaw). They often manifest as firm, sometimes irregularly surfaced masses within the gum tissue, and they are typically well-adhered to the underlying bone. While they can appear as a small, red, raised growth on the gums, they can eventually proliferate around nearby teeth and cause significant bone destruction beneath the visible mass. Though any dog breed can be affected, Golden Retrievers, Cocker Spaniels, Akitas, and Shetland Sheepdogs show a higher susceptibility, with diagnosis most common in dogs aged 6 to 10 years.
Recognizing the Signs
Several signs may suggest the presence of an oral tumor. A visible mass or swelling in the mouth is a common indicator, often appearing as a red or angry-looking growth on the gums that may grow around a tooth or teeth. Dogs might also experience difficulty eating, such as reluctance to chew, dropping food, or showing signs of pain while eating.
Increased drooling, sometimes mixed with blood, can be another symptom. Bad breath, medically known as halitosis, often accompanies oral tumors due to infection or tissue decay. Owners might also observe bleeding from the mouth, or notice that their dog’s teeth appear loose or have shifted from their normal position. Regular oral examinations can help in the early detection of these signs.
Diagnosis and Treatment Options
Diagnosis typically begins with a thorough oral examination by a veterinarian. Imaging techniques are employed to assess the extent of bone involvement. Dental radiographs, computed tomography (CT) scans, or magnetic resonance imaging (MRI) can provide detailed images of the jawbones and surrounding structures, helping to determine the tumor’s size and depth of invasion.
A definitive diagnosis relies on a biopsy, where a tissue sample is examined under a microscope by a pathologist. This analysis confirms the tumor type and helps rule out other oral conditions. Surgical removal is the primary and most effective treatment option.
The procedure involves the complete excision of the tumor, often requiring the removal of a portion of the jawbone (mandibulectomy or maxillectomy) to ensure wide, clean margins. One-centimeter margins of normal tissue around the tumor are recommended to minimize the chance of recurrence. In cases where complete surgical removal is not feasible due to the tumor’s location or size, radiation therapy may be considered as an alternative or adjuvant treatment. Bleomycin injection therapy is another less common option.
Prognosis and Long-Term Care
The prognosis for dogs with acanthomatous ameloblastomas is generally favorable, especially with early diagnosis and complete surgical removal. With successful surgical excision, the recurrence rate is low, reported to be around 5% following mandibulectomy or maxillectomy. However, if surgical margins are not clear, recurrence is possible.
Following surgery, regular post-operative check-ups are important to monitor the surgical site and the dog’s overall oral health. These examinations help detect any signs of recurrence or other oral issues. Maintaining good oral hygiene, as advised by the veterinarian, contributes to long-term health management. When radiation therapy is used, studies have shown an 80% survival rate at three years with no further tumor progression in some dogs.