Overview Salivary gland cancer is a rare disease in which malignant (cancer) cells form in the tissues of the salivary glands.
The salivary glands make saliva and release it into the mouth. Saliva has enzymes that help digest food and antibodies that help protect against infections of the mouth and throat. There are 3 pairs of major salivary glands:
• Parotid glands: These are the largest salivary glands and are found in front of and just below each ear. Most major salivary gland tumors begin in this gland. • Sublingual glands: These glands are found under the tongue in the floor of the mouth. • Submandibular glands: These glands are found below the jawbone.
There are also hundreds of small (minor) salivary glands lining parts of the mouth, nose, and larynx that can be seen only with a microscope. Most small salivary gland tumors begin in the palate (roof of the mouth).
More than half of all salivary gland tumors are benign (not cancerous) and do not spread to other tissues.
Symptoms Salivary gland cancer may not cause any symptoms. It is sometimes found during a regular dental check-up or physical exam. Symptoms caused by salivary gland cancer also may be caused by other conditions. Consult a doctor if any of the following problems occur:
• A lump (usually painless) in the area of the ear, cheek, jaw, lip, or inside the mouth. • Fluid draining from the ear. • Trouble swallowing or opening the mouth widely. • Numbness or weakness in the face. • Pain in the face that does not go away.
Treatment Different types of treatment are available for patients with salivary gland cancer. Some treatments are standard (the currently used treatment, often referred to as “standard of care”), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.
Three types of standard treatment are used:
Surgery Surgery (removing the cancer in an operation) is a common treatment for salivary gland cancer. A doctor may remove the cancer and some of the healthy tissue around the cancer. In some cases, a lymphadenectomy (surgery in which lymph nodes are removed) will also be done.
Even if the doctor removes all the cancer that can be seen at the time of the surgery, some patients may be given radiation therapy after surgery to kill any cancer cells that are left. Treatment given after surgery, to lower the risk that the cancer will come back, is called adjuvant therapy.
Radiation therapy Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated.
Special types of radiation may be used to treat some salivary gland tumors. These include:
• Fast neutron radiation therapy: Fast neutron radiation therapy is a type of high-energy external radiation therapy. A radiation therapy machine aims tiny, invisible particles, called neutrons, at the cancer cells to kill them. Fast neutron radiation therapy uses a higher-energy radiation than the x-ray type of radiation therapy. This allows the radiation therapy to be given in fewer treatments. • Photon-beam radiation therapy: A type of radiation therapy that reaches deep tumors with high-energy x-rays made by a machine called a linear accelerator. This can be delivered as hyperfractionated radiation therapy, in which the total dose of radiation is divided into small doses and the treatments are given more than once a day.
Chemotherapy Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the spinal column, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). The way the chemotherapy is given depends on the type and stage of the cancer being treated.