A Case of Lower Gingival Squamous Cell Carcinoma with Perineural Spread to the Cavernous Sinus and Orbit Caused by Mandibular Nerve Invasion

Abstract

A 57-year-old male with lower gingival carcinoma visited our hospital with chief complaints of occlusal pain in the left lower gingiva and numbness on the left side of the tongue. In 2012, neck dissection, left hemimandibulectomy, reconstruction with metal plates and ALT flap were carried out. Five months after surgery, diplopia of the left eye appeared. A tumor invading the cavernous sinus and orbit was identified by MRI. Chemoradiotherapy was performed. The patient developed systemic metastasis mainly to the spinal cord and died of respiratory failure 14 months postoperatively. In cases of tumor invasion to the mandible causing dysesthesia in the mandibular nerve area, the possibility of afferent invasion should be considered. Hence, assessment of brain nerves is an important factor in postoperative follow-up.