Carcinoma ex pleomorphic adenoma mimicking multiple facial nerve schwannoma

Carcinoma ex pleomorphic adenoma (CXPA) is a rare, aggressive, poorly understood malignancy that usually occurs in the salivary glands. CXPA has been reported to account for 3.6% of all salivary neoplasms and 11.7% of salivary malignancies. CXPA not only has a low incidence rate but there are few papers or case reports reporting perineural invasion rates. We report a case of CXPA which occurred in the parotid gland, showing retrograde perineural invasion along the facial nerve back to the internal auditory canal (IAC).