Clinical study of carcinomas of external ear canal and middle ear.

It is well known that the incidence of carcinoma in the external and middle ear is very low and that the prognosis is poor, especially for middle ear carcinomas.During the past 15 years, 11 patients with carcinoma of the middle or external ear have been treated in the Department of Otolaryngology of Hokkaido University Hospital. Seven carcinomas were in the external auditory canal and four in the middle ear. The histopathologic diagnosis was squamous cell carcinoma in eight, and adenoid cystic carcinoma in three patients. Therapy was mainly a combination of irradiation and surgical resection. Three patients also received CDDP.Our results revealed that the prognosis for external ear carcinoma is much better than for middle ear carcinoma. All four patients with middle ear carcinoma died, but five of the seven patients with external ear carcinoma are alive and free of the disease, at least one and a half year after surgery.Carcinoma of the external ear canal tended to show radial extension, involving the soft tissues adjacent to the canal rather than extending longitudinally towards the middle ear.The principal factor in the poor prognosis of middle ear carcinoma is ascribed to the destruction of the skull base, while that of the external auditory canal is deep invasion of the soft tissue around the canal.