Abstract
Cholesteatoma in the external ear canal is characterized by bony destruction of the canal wall and accumulation of debris. There have been a few reports on rediation - induced cholesteatoma of the external auditory meatus. We experienced 2 young patients with bilateral cholesteatoma in the bilateral external ear canal. The irradiation was reported to induce some bony changes such as resorption, replacement by fibrous tissue, ulceration, and cutaneous hyperkeratinization. It is generally believed that the cause of cholesteatoma in the external ear canal is migration disorder. In both cases, bilateral ears developed cholesteatoma 5 and 10 years after irradiation. If the external ears have been exposed in the irradiation field, we should observe them regularly with the possibilitiy of development of cholesteatoma, and cholesteatoma should be treated at its early stage.
