RESUMO
BACKGROUND: Radiogenic malignancies require cure of the primary disease and a prolonged survival. The introduction of high-volt technology in the 1950s and 1960s made radical radiotherapy feasible and successful in terms of higher cure rates and longer survival. We are already in a time when a higher number of patients with radiogenic secondary malignancies must be expected. CASE REPORT: A 12-year-old boy is reported who suffered from an advanced nasopharynx carcinoma and was treated with radical irradiation in 1983. 15 years later he developed a rare microcystic adnexal carcinoma of the auditory canal inside the volume of the target dose. The secondary malignant neoplasm was resected and required another radiation treatment (1 Gy b.i.d.) due to involved margins. DISCUSSION AND LITERATURE REVIEW: The entity of microcystic carcinoma is discussed with a review of the literature on biology, diagnosis, and treatment.