Conditions: Salivary Gland Tumors
We have three paired major salivary glands, the parotid, the submandibular, and the sublingual glands, as well as thousands of minor salivary glands. These can develop into benign or cancerous tumors (neoplasms), which are distinctly different from a swelling due to infection or trauma. Diagnosis of a salivary gland neoplasm is often confirmed with a biopsy, and imaging may be included in the evaluation. Treatment options depend on diagnosis, but generally include observation, medication, and surgery. Salivary gland tumors may be categorized according to the specific gland involved or by the type of tumor (based on appearance under a microscope), which generally predicts its behavior.
By gland:
A tumor in the tail of the parotid gland
Parotid gland tumors
The largest of the salivary glands are the left and right parotid glands, located in front of the ear, extending down just below the earlobe. As there are lymph nodes within the parotid glands, a lump in this area may be a lymph node, or it may be a tumor originating from the parotid gland itself. A benign growth of fat cells (lipoma) is also seen in the parotid gland on occasion.
Large submandibular mass
Submandibular gland tumors
The left and right submandibular glands sit under the jawbone, roughly near the lower canine or premolar tooth. In youth and young adulthood, these glands are not visible, but with age, they normally shift a little lower and show as a small lump under the jaw. A prominence in this area, especially if it is growing or asymmetric should be evaluated.
Glandular cancer from a minor salivary gland on the palate
Sublingual and minor salivary gland tumors
Thousands of minor salivary glands are dispersed throughout the oral cavity and thus tumors can arise from them on virtually any oral surface. The sublingual glands are located under the tongue, just under the surface lining. Tumors of these glands tend to be apparent from within the mouth, and a diagnostic biopsy is taken from oral surface. There are several types of lumps or bumps that can form within the mouth that are not technically neoplasms, such as inflamed areas and scars (fibromas) but when a true neoplastic growth does arise in one of these salivary glands, it has about a 50% chance of being cancerous.
By tumor type:
Pleomorphic adenoma
Overall the most common type of salivary gland tumor, this benign neoplasm typically grows indefinitely. If neglected over years or decades, a pleomorphic adenoma does have the potential to transform into a cancer (called “carcinoma ex-pleomorphic adenoma), which, becomes more aggressive in growth and can spread to other parts of the body.
Warthin’s tumor (cystadenoma lymphomatosum)
Warthin’s tumor, also known as cystadenoma lymphomatosum, is a benign salivary gland tumor usually found in the parotid gland, and it is not unusual for people to have this this type of tumor on each side. Tobacco smoking is a significant risk factor for the development of a Warthin’s tumor.
Lymph node within a salivary gland
Lymph nodes exist within the parotid salivary gland and near the submandibular salivary gland. As with lymph nodes elsewhere, these lymph nodes may be involved with spread of cancer from another site (such as a squamous cell carcinoma from the scalp, temple, face, or ear spreading to a node within the parotid or an oral squamous cell cancer spreading to a node within or adjacent to the submandibular gland), or a tumor originating in the lymph nodes (lymphoma).
squamous cell carcinoma
Squamous cell carcinoma is a common type of cancer of the skin or lining of the mouth or throat. When squamous cell carcinoma is present in a salivary gland, it usually has gotten there by spread from a cancer starting in the skin, mouth, or throat, and then spreading to a lymph node within the salivary gland.
adenoid cystic carcinoma
Adenoid cystic carcinoma is a type of salivary gland cancer known for its predisposition to spread along nerves. The main tumor mass may be seen and felt, but microscopic tracking along nerves that pass through the area can be extensive.
acinic cell carcinoma
Acinic cell carcinoma is a slow growing salivary gland cancer that is known for its potential to spread to the lungs and grow there so slowly that detection may occur decades after the salivary gland primary tumor has been treated.
Lipoma
A lipoma is a benign tumor of fat tissue, and is generally soft to the touch, painless, and somewhat moveable. These can occur in any fatty tissue of the body, including in the head and neck area. Lipomas are not strictly salivary gland tumors, but may occur so close to a salivary gland tumor as to be a diagnostic consideration when a mass is present where a salivary gland is located. The cancerous analog of a lipoma, called a liposarcoma, is very rare.
Benign lymphoepithelial cysts
These benign cysts are uncommon in the general population, but present in about 5% of HIV patients, nontender one or both sided parotid gland enlargement associated with dry mouth, resulting in dry atrophy of the oral tissues, cavities, and inflammation of the mouth.