It is well recognized that radiation can be carcinogenic for a wide variety of tumors, especially, in breast, thyroid, and bone marrow which appear to be radiosensitive. The criteria for establishing the dignosis of radiation- induced malignancy are the knowledge of prior irradiation and the appearance of a malignancy in the irradiated area. We report a case of carcinoma of the thyroid and esophagus following prior neck irradiation for thyroid mass.