There are at least six kinds of malignant tumors and about the same number of benign ones. The treatment is different for each kind of tumor, so expert pathologic study is necessary.
Twenty-five percent of parotid tumors, 40 percent of submandibular tumors, 95 percent of sublingual tumors and 50 percent of minor salivary gland tumors are malignant.
The most common site of malignant tumors is in the parotid glands. The most common site of tumors of the minor salivary gland tumors is in the palate . These tumors can also occur anywhere in the mouth, the pharynx, larynx and paranasal sinuses.
Salivary gland cancers are caused mainly by the heavy use of tobacco. Increased incidence is also associated with previous radiation exposure to the head and neck. Radiotherapy was used to treat acne during the 1930s, 1940s and 1950s, with a resulting five to eight times higher risk of developing cancer of these salivary glands.
Treatment Overview Early-stage, low-grade salivary gland tumors, especially tumors of the parotid gland, are usually curable by surgery. Large, bulky or high-grade tumors have a poorer prognosis and often receive postoperative radiotherapy. Tumors that cannot be completely removed surgically or that recur may be treated with radiotherapy or respond to chemotherapy .
Prognosis also depends on which gland is involved, the microscopic pattern, the grade of malignancy, the stage and whether the tumor has extended to involve the skin, lymph nodes , nerves or distant sites.
