An Unusual Morphology of a Pleomorphic Adenoma.

We present a case of a deep lobe parotid pleomorphic adenoma extending into the parapharyngeal space via an unusual morphology. This is a single patient case report of an unusual morphology with an associated review of the literature. The patient successfully underwent right parotidectomy during which it was seen that the tumor was extending above rather than through the stylomandibular tunnel, an unusual morphology for a pleomorphic adenoma. Despite the classic teaching that deep lobe parotid tumors reach the parapharyngeal space by traveling through, or below, the stylomandibular tunnel, it is possible for tumors to occur outside this tunnel. Recognition that this unusual growth path, although rare, can occur is important when designing an appropriate surgical resection.