Radiation carcinogenesis: An unusual familial occurrence of neoplasia following irradiation in childhood for benign disease

A patient is presented who developed a mucoepidermoid carcinoma of the parotid gland 30 years after irradiation to the area for benign disease. Family history revealed four siblings had likewise developed neoplasia in locations previously irradiated for benign disease. Types of neoplasia included basal and squamous cell carcinoma of the skin, thyroid adenomata, and benign mixed tumor of parotid gland. The patient's mother, occupationally exposed to irradiation, developed acute monocytic leukemia. Comparison of these findings with those in the literature is presented.