Unilateral parotid agenesis associated with pleomorphic adenoma of ipsilateral accessory parotid gland.

Congenital agenesis of the parotid gland is rare, and its association with accessory parotid tissue is even rarer. We report an unusual case of unilateral agenesis of the left parotid gland associated with pleomorphic adenoma of the left accessory parotid gland. To best of our knowledge, this is only the second such published case in the literature.