Because of the anatomy of the floor of the mouth, radiation therapy is often used alone. Distant metastases are uncommon, so chemotherapy is not often used. When metastases are present, they usually are found in lung, bone, heart, and pericardium. Occasionally, when cystic, they are firm. Malignant transformation is possible, resulting in carcinoma ex mixed tumor.
Treatment is surgery.
The recurrence rate is high when excision is incomplete. Other benign salivary gland tumors include monomorphic adenoma, oncocytoma, and papillary cystadenoma lymphomatosum. These rarely recur or become malignant. They are firm, nodular, and usually fixed to adjacent tissue, but they often have a poorly defined periphery. Pain and neural involvement are common, and eventually, the overlying skin or mucosa may become ulcerated.