IN-SITU BREAST-CARCINOMA AFTER TREATMENT DURING ADOLESCENCE FOR THYROID-CANCER WITH RADIOIODINE

We reviewed the courses of patients treated during childhood or adoles cence for thyroid cancer to estimate the frequency of, and to identify possible risk factors for, the occurrence of second malignant tumors in this population. We identified all patients treated for thyroid can cer in a cohort of 1,406 pediatric cancer patients who were diagnosed prior to 20 years of age during the period January 1, 1960 through Dec ember 31, 1988 and who were treated at Roswell Park Cancer Institute. Twelve patients were treated for thyroid cancer, of whom nine were wom en. In situ breast carcinoma was diagnosed 25 and 26 years after diagn osis of thyroid cancer in two of four women treated with radioiodine. No new cancers were diagnosed in the five women treated with thyroidec tomy only. Two of four women treated for thyroid cancer during adolesc ence with radioiodine, which is concentrated in the breast as well as other organs, developed in situ breast carcinoma. Review of a large co hort of adolescent female thyroid cancer patients treated with radioio dine is necessary to provide an accurate estimate of their risk of dev eloping breast cancer. These patients must remain under medical survei llance throughout their lifetimes to facilitate prompt diagnosis of an d early intervention for new conditions, such as the occurrence of bre ast cancer. (C) 1995 Wiley-Liss, Inc.