The most common type of malignant pleomorphic adenoma is carconoma in pleomorphic adenoma. However, the other type has sometimes been reported, which reveals malignant changes on both epithelial and stromatous cells. This paper contains a rare case of malignant pleomorphic adenoma.
A 53-year-old man visited our hospital with complaint of the swelling of the right mandibular region. The tumor was surgically removed under the diagnosis of the malignant tumor of submandibular salivary gland. However it proliferated again and metastasis was found on the nasal septum. The patient died of general-condition exacerabation after 18 months.
Histologically the tumor consisted of the solid nests of epithelial cells and partially of adenomatoid and squamous cells. Myxomatous or hyalin areas were also seen. Cellular atypia were observed on both epithelial and myxomatous cells.
Autopsy showed metastasis in the nasal septum and lung and small round cell carcinoma was found in the lung.