Mixed tumors of the parotid gland (or pleomorphic adenoma) are common parotid tumors that originate from the epithelial tissue of the gland, but often contain mucus and cartilage-like tissue in addition to epithelial components, so they are called mixed tumors. Parotid mixed tumors can occur at any age, but are more common in middle-aged people between 30 and 50 years old, with no significant difference in incidence between men and women. The tumor is mostly a solid mass of medium hardness in the parotid area (under the ear or in front of the ear), with a nodular (or smooth) surface, clear borders, pushable, non-adherent to surrounding tissues, no pressure pain, no obvious conscious symptoms, slow growth, and a course of several months to several decades. If the tumor has one of the following conditions, it should be considered to have the possibility of cancer, and the patient should receive surgery as soon as possible: 1.Tumor growth suddenly accelerates recently, and the tumor body (mass) increases significantly. 2. The mobility of the tumor (mass) is reduced, or even fixed and cannot be pushed. 3.Tumor and local skin show symptoms of abnormal sensation such as scratching, insect crawling sensation and pain. 4.Facial paralysis occurs on the same side. 5.Mixed tumor of parotid gland is prone to recurrence after surgery due to incomplete envelope (such cases are mostly caused by irregular surgery), and the incidence of cancer increases greatly in patients with multiple recurrences, so such patients should also receive regular surgery as soon as possible.