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Malignant degeneration of pleomorphic adenoma--clinical implications
1St Joseph Hospital, Atlanta, GA.
Introduction:
The incidence of carcinoma arising in a pleomorphic adenoma is reportedly between 1.4% and 6.3%. Malignant degeneration is often associated with a prolonged history of untreated or recurrent pleomorphic adenoma.
Materials And Methods:
Two patients with malignant parotid carcinoma that arose from benign pleomorphic adenoma are reviewed.
Results:
Both patients exhibited a prolonged history of pleomorphic adenoma apparently persistent after initial inadequate surgery. Surgeries were performed 37 and 12 years before development of malignancy.
Discussion:
The phenomenon of malignant carcinoma arising from benign pleomorphic adenoma is an important issue. The occurrence of these malignant carcinomas emphasizes that aggressive treatment of primary and recurrent mixed tumors is necessary.
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