IT HAS been approximately seven years since radioactive iodine was first used in therapeutic amounts in the treatment of thyroid carcinoma. Although this period is too short for any final evaluation, it has been long enough to enable the physician to formulate definite criteria for its administration. The original enthusiasm for treating all thyroid cancers with I131 has now been rightfully replaced by an investigative approach to each individual case. Since the limitations of I131 therapy are many, no patient should be denied other therapy of proved value in the hope that therapeutic doses of radioactive iodine will bring about lesion resolution.
We report our experiences with 47 consecutive cases of thyroid carcinoma in a representative university center over a four-year period. For clinical purpose the lesions are microscopically classified into papillary, adenomatous, and undifferentiated carcinomas. There were 13 cases of papillary carcinoma, usually with a few adenomatous