Perineural tumor spread involving the central skull base region.

Perineural spread of tumor is defined as extension of the primary tumor along tissues of the neural sheath (epineurium and perineurium) of a named nerve. Given the density of cranial nerves in the central skull base region and their extracranial communications, perineural tumor spread from a variety of sources can affect the central skull base region. Common malignancies with perineural tumor spread to central skull base include mucosal squamous cell carcinoma, adenoid cystic carcinoma, and cutaneous malignancies including melanoma. The presence and extent of tumor spread influence selection of treatment and prognosis. Appropriate imaging and interpretation, therefore, play a crucial role in detection and management of perineural tumor spread in the central skull base region.