Ameloblastoma

What is ameloblastoma?

Ameloblastoma is a rare, slow-growing tumor that develops in your jaw. Ameloblastomas grow from the same type of cell that forms your tooth enamel. About 80% of the time, it develops in your lower jaw in the space behind your back teeth (molars).

Ameloblastomas are benign (noncancerous). But ameloblastomas aren’t benign in the way most people may think of the word, as in harmless. They can grow big enough to change the structure of your jaw or damage your teeth. They can also recur (return) after treatment.

Early treatment and careful monitoring after treatment can prevent an ameloblastoma from damaging your jaw.

Types of ameloblastoma

At first glance through a microscope, all ameloblastoma cells look like tiny honeycombs or soap bubbles. Healthcare providers study the cells closely to classify ameloblastomas into types, including:

• Conventional ameloblastoma. Conventional ameloblastomas represent 85% of all ameloblastomas. These tumors grow more quickly than the other types and are likely to spread from your jaw to other nearby areas of your mouth.
• Unicystic ameloblastoma. These tumors are less likely to spread beyond your jaw than conventional ameloblastomas.
• Peripheral (extraosseous) ameloblastoma. Researchers believe these tumors likely spread to your jaw from your lower gum or soft tissue in your mouth. They grow more slowly than conventional and unicystic ameloblastoma.

Although extremely rare, ameloblastoma can be (or become) malignant. Types include:

• Metastasizing ameloblastoma. These tumors look like benign ameloblastoma beneath a microscope. In reality, they’re a form of metastatic cancer. Metastatic cancer spreads from a tumor to other parts of your body. A provider may not know that an ameloblastoma is metastatic until they find that the cancer has spread to your lungs, brain or skin.
• Ameloblastic carcinoma. These tumors may start as cancer. Or they may start off as benign ameloblastomas and then become malignant.

How common is ameloblastoma?

Ameloblastomas are one of the most common benign jaw tumors, but they’re still rare overall. Studies estimate that every year, only 1 in 1 million people is diagnosed with ameloblastoma. And only 2% of those people have malignant ameloblastoma.

Anyone can develop ameloblastoma, but the condition is more common in people from ages 30 to 60. Diagnoses are more common in Africa and Asia.

What are the symptoms of ameloblastoma?

Ameloblastomas grow slowly. You can have an ameloblastoma for 10 to 20 years before you or a healthcare provider notice an issue. As the tumor grows and invades tissue, you may notice changes in the shape of your face and jaw or problems with your teeth.

Signs and symptoms of ameloblastoma include:

• Painless swelling in your jaw that only affects one side of your face.
• A new growth that looks like you’ve tucked nuts or small balls inside your cheek.
• Teeth with pink or red spots or that chip and shatter easily.
• Difficulty moving your jaw.
• Red and swollen gums.
• A misaligned bite (malocclusion).
• Loose teeth.

What causes ameloblastoma?

Ameloblastomas form when the cells that create your tooth enamel (ameloblasts) keep growing even after your enamel is in place. Experts don’t know why this happens.

Recent studies show that many people with ameloblastoma have common genetic mutations associated with cell division problems that fuel tumor growth. Mutations involving the BRAF and SMO genes are common with ameloblastomas.

Experts are currently researching these mutations to identify treatments that target the abnormal cell changes (targeted therapy) and destroy tumor-causing cells.

How is ameloblastoma diagnosed?

Your dentist may spot a potential ameloblastoma while taking X-rays as part of your regular dental check-up. They’ll refer you to a specialist for additional tests if they suspect an issue. Those tests may include:

• Imaging tests: You may need additional X-rays and other tests, like magnetic resonance imaging (MRI) and a computed tomography (CT) scan, to show the tumor’s location and size. These tests can help your provider rule out other tumors that look like ameloblastoma. You may need a positron emission tomography (PET) scan to look for cancer spread (with malignant types).
• Biopsy: A biopsy allows your provider to collect tissue from the tumor so a pathologist can examine its cells beneath a microscope. The type of cells helps your provider identify the type of ameloblastoma, so they know the best treatments.

How is ameloblastoma treated?

Surgery that removes the tumor and some nearby tissue (enough to ensure no abnormal cells remain) is the best treatment for ameloblastoma. Healthcare providers classify tumor surgeries as radical or conservative:

• Radical surgery: Most people with ameloblastomas need radical surgery. Your provider will remove the tumor and a large amount of bone and tissue to reduce the chance of your tumor growing back. They may remove part or all of your lower jaw (mandibulectomy) or all or part of your upper jaw (maxillectomy).
• Conservative surgery: Your provider will remove your tumor and a small amount of healthy tissue and bone. Conservative surgery may be an option if your tumor is small and unlikely to invade nearby bone and tissue.

If you’re not a candidate for surgery, your provider may recommend radiation therapy to get rid of the tumor. Or you may need radiation therapy after surgery to destroy any remaining tumor cells. This treatment directs high-powered X-rays toward the tumor to kill cells.

Additional treatments following surgery

Radical surgeries for ameloblastomas usually require a lengthy recovery period (several months). Afterward, you may need additional treatments to get back to feeling like yourself again.

You may need:

• Reconstructive surgery: You may need to work with a plastic surgeon to restore the appearance of your face and jaw. These procedures involve transferring bone from one part of your body (like your hip or your shoulder blade) to rebuild your jaw.
• Dental implants: You may need prosthetics (like false teeth) to replace the ones that your provider removed during surgery. These devices can help you regain your ability to chew. They can also restore your confidence in how your mouth looks.
• Speech therapy: A speech-language pathologist can help you adjust to the changes in your jaw and face so you can chew, eat and speak.
• Nutrition guidance: A dietitian can help you choose nutritious foods that are easy to chew and swallow while you’re healing.

How can I reduce my risk of developing ameloblastoma?

There’s no way to prevent ameloblastoma. But you can catch growths early by seeing your dentist every six months for check-ups and oral cancer screenings. Early treatment can prevent an ameloblastoma from damaging tissue in your jaw and face.

What can I expect if I have this condition?

Your prognosis, or expected outcome, depends on your health, the type of ameloblastoma, where it’s located and the kind of surgery to remove the tumor.

Most people treated for ameloblastomas will need life-long monitoring to check for recurrences. Ameloblastoma grows back after surgery in up to 20% of people. More than half of the time, tumors recur within the first five years after surgery.

Ask your healthcare provider about how often you’ll need monitoring to check for tumor regrowth.

What happens if ameloblastoma is left untreated?

Ameloblastomas can damage important structures in your face and jaw and can even be fatal without treatment. Left unchecked, tumors can cause facial disfigurement and make it difficult to chew and swallow. With continued growth, they can invade tissue in your brain and central nervous system and block airways.

Seeking treatment for an ameloblastoma can prevent these worst-case scenarios from happening.

When should I see my healthcare provider?

Make sure you understand how often you’ll need follow-up visits after treatment to check for recurrences. Unfortunately, many ameloblastomas can come back years after your surgery. If an ameloblastoma comes back, your provider can recommend new treatments to prevent it from damaging your jaw and face.

When should I go to the emergency room?

Your healthcare provider will talk to you about what you can expect as you recover from surgery. But you should go to the emergency room if:

• You have a fever higher than 101 degrees Fahrenheit (38.3 degrees Celsius).
• You have pain that doesn’t improve with the medications your provider prescribed for you.
• You have more drainage or swelling than you expected.
• You have shortness of breath or a feeling that you can’t catch your breath.

What questions should I ask my healthcare provider?

Ameloblastoma is a serious medical condition that requires major surgery. Here are some questions you may want to ask as you and your healthcare provider discuss your treatment:

• What type of surgery will I need?
• Why do you recommend that surgery?
• Will I need treatments in addition to surgery to get rid of the tumor?
• Will I need plastic surgery or speech therapy?
• What are possible complications or side effects?
• How likely is it that the ameloblastoma will return?