IN 1940 Hamilton, Soley and Eichorn1 described a method of localizing administered radioactive iodine in the human thyroid. Patients were given an oral tracer dose of radioactive iodine prior to operation. Histologic sections were made of the excised portion of the gland and the secretions placed in contact with unexposed photographic film. Areas of uptake of radioactive iodine in the section produced a blackening on the film. With this technic, these authors found the greatest uptake of iodine in areas of hyperplasia. Of great interest was their observation that the carcinomatous tissue in two thyroid studies showed no uptake. Since their publication, there have been a few reports of thyroid carcinomas showing appreciable uptake of iodine.
These authors also noted that the concentration of radioactive iodine was great in the more cellular regions of the thyroid and did not show any predilection for the colloid. LeBlond2 in 1942,