Recurrent lower gingival squamous cell carcinoma spreading along the pathway of the inferior alveolar nerve.

Computed tomography images showed recurrent lower gingival squamous cell carcinoma spreading from the mandibular foramen to the middle cranial fossa. This extensive tumor spread followed exactly the same anatomic pathway as the inferior alveolar nerve. Histopathologic examination revealed squamous cell carcinoma. Tumor spread was thought to be caused by perineural invasion. This case demonstrates computed tomography features of perineural tumor spread along the inferior alveolar nerve.