The salivary gland is one of three pairs of glands that secrete saliva. Saliva helps the body break down food for digestion. Salivary gland tumors are growths in the tissues of these glands.
There are three pairs of major salivary glands. The first and largest pair is the parotid glands. They sit in front of and just below the ear. The second largest pair is the submandibular glands. These sit under the side of the jaw. The sublingual glands sit under the tongue in the floor of the mouth. Scattered below the lining of the mouth and throat are minor salivary glands. Each of the glands secretes saliva into the mouth through ducts.
Salivary gland tumors can arise from the cells in the glands, the ducts, or the supporting structures not involved in saliva secretion. These growths can be cancerous or noncancerous. Approximately 80% of salivary gland tumors occur in the parotid gland.
Most of salivary gland tumors are harmless. Usually they are slow growing, non-tender, painless bumps. They are often single masses with distinct edges.
But sometimes the tumors are cancerous. In these cases, the masses do not have distinct edges and appear to be stuck to surrounding tissues. Often they affect nearby nerves, causing a loss of feeling or function of the face or tongue. The tumors may grow quickly, feel lumpy, and cause pain.
Tumors arising from minor salivary glands usually present as painless, slow-growing swellings below the lining of the cheek or hard and soft palate.
The cause of salivary gland tumors is unknown.
There are no known ways to prevent salivary gland tumors.
Initial diagnosis is based on physical examination and the location of the mass within or arising from the salivary glands.
A fine needle aspiration biopsy is usually performed. With this procedure, a fine needle is used to remove cells from the growth for examination. It can then be determined whether or not the mass is cancerous and how it can be treated. The larger the gland is where the growth appears, the more likely it is not cancer-related.
If the mass is cancerous, a CT scan of the neck and face is usually performed. This will help discover the extent of the tumor and whether it has spread.
For tumors that are not cancerous, the only long-term effects are generally cosmetic. If the tumor prevents saliva from draining, symptoms of blockage or infection may occur. This would include uncomfortable swelling after meals that improves over several hours. Complete blockage would also cause constant pain.
The long-term effects of the cancerous tumors vary based on the type of cancer involved. If untreated, they could lead to death.
Salivary gland tumors are not contagious and pose no risk to others.
For noncancerous growths, monitoring is appropriate. It may be necessary to remove some forms of noncancerous tumors if they look like they may become cancerous. Depending on the recurrence rate associated with the type of tumor and its location, all or part of a gland is sometimes removed.
For cancerous tumors, treatment depends on the type of cancer involved. Treatment may involve removal of a portion of the gland, or the entire gland. Salivary gland tumors can spread to nearby lymph nodes. If this occurs, a radical neck dissection is necessary. A neck dissection is an operation that is done for individuals with cancer of the head and neck.
The purpose is to remove the lymph nodes in the neck Radiation therapy may also be used to treat salivary gland tumors. To date, there are no effective chemotherapy protocols for salivary tumors.
There are possible side effects with any surgery. These include bleeding, infection, and reactions to anesthesia. Another side effect is nerve damage. This could cause a loss of feeling or function of the face or tongue.
If radiation therapy is needed, damage to any remaining salivary glands may occur. This is accompanied by dry mouth and problems with dental cavities.
Noncancerous tumors do not require further treatment. Cancerous growths may or may not need further treatment, depending on the type of tumor. Follow up also depends of the type of tumor. More aggressive tumors require longer periods of follow up. Less aggressive tumors do not need as regular or as prolonged a follow up.
If a person has a cancerous salivary gland tumor that has been treated, he or she should exam his or her neck regularly. Any new or worsening symptoms should be reported to the healthcare provider.
Tierney, Lawrence, editor, "Current Medical Diagnosis and Treatment, 39th edition", 2000
The Merck Manual of Medical Information, 1997