Reported is a case of squamous cell cartinoma of the lower lip that spread along the inferior alveolar nerve to the cranium, and also retrogradelly spread down to the other divisions of the fifth nerve.
One year after radical operation of the primary lesion, the patient began to have the sensation of something chewing his tongue. This was 2 months before observation of a recurrent mass around the mental foramen region. Roentgenograms revealed widening of the mental foramen, the mandibular canal, and the foramen ovale. Invasion of cancer through nerve sheath was suspected because of these findings. Hemimandiblectomy was carried out 48 days after the recurrence. A frozen section was applied in order to secure the surgial margin during the surgicl procedure. Histopathologically the inferior alveolar nerve, the mandibular nerve just under he foramen ovale, the lingual nerve and the mylohyoid nerve revealed invasion by the cancer.
After the operation, as the spread of the cancer into the cranium was suspected, 60Co therapy including the base of the skull was tried, but the patient died 34 months after initial inspection.
Attention is again called to the fact that spread of carcinoma along nerve sheath is a common pattern.
