Carcinoma associated with irradiation of the immature breast.

In two women who had undergone radiation therapy at ages one and eleven years, respectively, carcinoma in a hypoplastic breast developed. Each patient was treated by radical mastectomy. One patient is presently being followed without evidence of metastases; the other died of sarcoidosis following thoracotomy. A history of irradiation, hypoplasia and microscopic findings compatible with radiation changes suggests that these two cases of carcinoma may be radiation-induced.