Medically Reviewed by Dr. K. Updated as of April 4, 2021.
What Is Adenoid Cystic Carcinoma?
Adenoid cystic carcinoma is a rare cancer that generally begins within the glands that produce saliva in the mouth. These glands are present under the tongue, within the jaw. This cancer can also occur within other parts of the mouth and throat, even in other areas of the body like sweat glands or tear glands.
Adenoid cystic carcinoma is the third most common malignant salivary gland tumour. It affects women more than men and can occur at any age between teenage years and 80 years old.
It is quite slow-growing, and can occasionally spread to other parts of the body before any symptoms become evident. It can reoccur in areas that have received treatment, or even occur at other areas via spreading, i.e. to the liver, lungs, and bones where it becomes a more serious disease.
The underlying cause of adenoid cystic carcinoma is not known, but it may be linked to carcinogens like asbestos or pollution.
Symptoms of the disease include the following:
- A lump on the roof of the mouth, under the tongue, in the bottom of the mouth, or inside the cheek
- An abnormal area on the lining of the mouth
- Numbness of the upper jaw, palate, face, or tongue
- Difficulty swallowing
- Hoarse voice
- Dull pain
- A bump or nodule in the front of the ear or underneath the jaw
- Paralysis of a facial nerve
If you have any of the above symptoms, see your doctor for immediate medical attention.
After taking a complete history, including family history, your doctor will complete a thorough physical examination. Following which, a biopsy of the lump will be taken. A small sample will be examined to look for signs of cancer.
After this, further imaging must be done to check for signs of spread throughout the body and to look for any structural organ damage. Imaging may include:
- Computerized tomography (CT) scan: these a multiple X-Rays taken at different angles to combine into a view of the entire body
- Magnetic resonance imaging (MRI): these show an extremely clear image of soft tissue within the body
- Positron emission tomography (PET) scan: radioactive substances are used to produce a 3-dimensional image
The main treatment includes surgery to remove the tumour as well as a small margin of surrounding tissue. This is often followed by radiation therapy.
Adenoid cystic carcinoma is a rare cancer that spreads via nerves, rather than via lymph nodes. Because of this, the nerves surrounding the tumour must be examined to ensure no cancerous tissue is damaging them. On occasion, damaged nerves must be surgically removed. This means that the face may droop after surgery as the affected area will no longer be able to move.
Other times, the voice box may need to be surgically removed, depending on the spread of the cancer.
Radiation treatment may also be used in the treatment process. The following are 3 radiation treatments that may be used:
- External beam radiation: focused high-energy protons or x-rays directed at cancerous cells
- Brachytherapy or Internal radiation therapy: small radioactive “seeds” will be placed near cancerous cells
- Neutron therapy: targets small tumours by heating up cells with up to 100 times more energy than normal radiation treatment
Radiation treatment focused on areas of the head and neck can have local side effects including pain, dry mouth and difficulty swallowing. It is important to discuss all treatment options and side effects with your doctor prior to deciding on a plan.
What to Expect
The 5-year survival rate of adenoid cystic carcinoma is approximately 89%. The 15-year survival rate reduces to 40%. Recurrence, cancer that returns after treatment, often occurs in the lungs, and can reoccur many years after initial treatment.
Regular checkups are vital after treatment to look for recurrence. These checkups may involve further imaging including x-rays, CT scans, MRIs and PET scans.
Referenced on 2.3.2021:
- American Cancer Society: “What is salivary gland cancer?"
- Adenoid Cystic Carcinoma Organization International.
- Adenoid Cystic Carcinoma Research Foundation.
- American Society of Clinical Oncology: “Adenoid cystic carcinoma."
- The Oral Cancer Foundation: “What is adenoid cystic carcinoma?"
- National Organization for Rare Disorders: “Adenoid Cystic Carcinoma."
- Rodrigues Graca, S. BMJ Case Reports, August 2012.
- Cancer.net: “Adenoid Cystic Carcinoma: Treatment Options."