Parotid tumors are abnormal growths of tissue in the parotid gland — the largest of three major pairs of salivary glands in the mouth and throat. The parotid glands secrete saliva into the mouth, thereby making it easier to chew, swallow, and digest food. One gland is situated below each ear, beneath the jawbone. Tumors of the gland typically increase its size but tend to grow rather slowly. When parotid tumors are diagnosed as malignant, they can usually be successfully treated.
Salivary gland tumors are generally quite rare, typically occurring in as few as one in 33,000 people each year. When such tumors do develop, however, they usually manifest themselves as parotid tumors. About 80 percent of parotid tumors are normally diagnosed as benign, or noncancerous.
The first symptom of a parotid tumor is often swelling of the gland, noticed as a hard bump below the ear. Enlargement is typically accompanied by little or no pain. Since the facial nerve runs through the parotid gland, pressure on the nerve may eventually result in an additional symptom — some degree of difficulty in moving the muscles of the face on the side of the affected gland.
Tests to see if a tumor is benign or cancerous typically begin with a biopsy to examine tissue, usually in the form of a fine needle aspiration (FNA). If additional tests are needed for diagnosis, they generally consist of one or more imaging studies using x-rays, computed tomography (CT), magnetic resonance imaging (MRI), or positron emission tomography (PET) scans. When a malignancy is detected, further imaging studies are sometimes conducted to determine if cancer cells have spread to the lymph nodes.
Whether parotid tumors are malignant or benign, the primary treatment option is normally surgical removal of the tumor. The surgery usually involves some risk of after effects since the surgeon must cut around the easily damaged facial nerve. Candidates for this surgery are generally advised to ask their surgeons for an assessment of possible facial nerve damage and its consequences.
For cases where a cancerous tumor appears to be particularly aggressive or has already spread to the lymph nodes, the surgeon may also remove the lymph nodes. Such surgeries are frequently supplemented with radiation therapy. In rare instances when chemotherapy is used to treat malignant parotid tumors, its use is generally limited to shrinking the tumors to reduce pain.
Even when parotid tumors have been diagnosed as malignant and the lymph nodes are involved, the cancer is usually curable. Curability of cancer is assessed in terms of five-year survival rates. Even for malignant parotid tumors in which cancer has spread to the lymph nodes, survival rates ranging up to 85 percent can typically be expected following treatment.