The case of a 57-year-old woman with a malignant schwannoma originating from the aural region is reported. Her symptoms were left otorrhea and hearing loss of five years duration associated with left facial paralysis. Histopathological examination from a previous operation done elsewhere under the diagnosis of cholesteatoma revealed malignant schwannoma. The patient was treated by irradiation (Lineac x-ray 5, 000 rad) and chemotherapy. However, her headache gradually increased, craniotomy was performed but the patient died from meningitis one month postoperatively. Postmortem microscopic examination revealed that spindle-shaped cells had the pattern of interlacing bundles, in part, with atypical nuclei. Electron microscopically, the tumor cells were spindle-shaped with atypical nuclei, rough chromatin and clear nucleolonema. In cytoplasm, rough ER and Golgi apparatus were seen to be moderately developed, and mitochondrias were not abundant. Discontinuous basement membrane was also observed. Malignant schwannoma in the head and neck region is comparatively rare. Its histological diagnosis is often difficult because of the absence of characteristic features.
