Recurrent salivary gland pleomorphic adenoma: etiology, management, and results

Recurrence of salivary pleomorphic adenoma is an uncommon event, if the primary surgery has been performed meticulously and the tumor has been completely excised. The parotid gland is the most frequent site for recurrence followed by the minor salivary gland (oral cavity) and then the submandibular gland. Recurrences are classified as uninodular or multinodular. The uninodular recurrences are more easily treated by “completion” surgery and removal of the remaining glandular structure. Multinodular recurrence is more diffuse and hence surgery is likely to be more extensive, with risk of resultant permanent facial nerve paralysis, the possibility of further tumor recurrence, and the long-term risk of malignant degeneration. The use of radiotherapy remains controversial in the management of benign recurrent disease; although its use may minimize the surgical complications, the risk of malignant degeneration persists and complications are associated with radiotherapy.