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The surgical approach to recurrent pleomorphic adenoma of the parotid gland.

This is a retrospective study of 19 patients who were referred to the Department of Otolaryngology, Edinburgh Royal Infirmary with recurrent pleomorphic adenoma of the parotid gland. In the majority of patients, a superficial parotidectomy was performed as primary treatment. Recurrence of the tumour was either due to tumour implantation or inadequate surgical excision. Permanent facial paralysis occurred in three patients after revision parotidectomy. Change from pleomorphic adenoma at first operation to carcinoma in pleomorphic adenoma (malignant mixed tumour) at the second was noted in three patients who are still alive and free of recurrent tumour. Eighteen out of the 19 patients did not have further recurrences after revision parotidectomy. The surgical principles in the prevention of tumour recurrence and revision parotidectomy are discussed.