Worid J. Surg. Vol. 16, No. 1, Jan./Feb. 1992 132 rm 7 Th q ent: we rrr ae in Peae eeY! titeSy “es Fig. 4. An example of an atypical lesion in the thyroid of an 18 year old female exposed on Ailingnae at age 2. This atoll received less radioactive fallout than Rongelap. A. Thesize of this lesion maybe appreciated by comparison with the size of the normalfollicles. Although the lesion is very small, its configuration suggests that the developing capsule around the lesion has already been breeched by proliferating cells forming a secondary lobulation at one end. (x75). B. Higher magnification of the lesion in A. to illustrate the detail of the cells. This lesion is composed of cells with manybizarre and giant nuclear forms with some prominantnucleoli and some mitotic figures. The lesion was considered an atypical adenoma by the panel. It would seem that this lesion was so small that it had not yet declared its potential to metastasize. It is classified as an atypical adenoma. (< 255). showed bizarre nuclear forms, hyperplasia, and what some considered to be capsular invasion; however, in view of the presenceofscar tissue from previous surgery such lesions were not classified as carcinomas but atypical adenomas(Figs. 7 and 8). Figure 8B, for instance, shows probable capsular invasion with marked cellular atypia. Anotherlesion (Fig. 8C) from the same individual shows marked papillary structure. In the third reoperated case there were atypical lesions found (Fig. 9), as had been present t0 years before. Perhaps in retrospect, some of these operations should have been total thyroidectomies at the first operation. There were 3 other cases (not reported here) which required a second operation, but for different circumstances. In 2 patients the removal the remnant of a lobe, 3 days and 3 months respectively, was indicated because a lesion was origionally thought to be benign at the time of surgery but later (with additional study and consultation) was judged to be carcinoma. The third case was reexplored because a lymph node had becomepalpable 5 years following wide removal of a carcinoma with positive lymph nodes. Fortunately there was no recur- radiation fallout, comparable to cases reported by others [21!27] from roentgen rays. The fact that no lesions were palpated during annual examinations for 9 years following the fallout indicates that there was an extended latent period following exposure. It seems significant that the first lesions began to appearin the most heavily exposed population (Rongelap) and that it was in the children of that group that the lesions developed first. Later, lesions began to appear in the lesser exposed groups (Ailingnae and Utirik}. Thus, the latent period seemed to be related to the degree of exposure. Mention has been made of the nodular hyperplasia of the thyroid in 9 of the first 14 individuals operated [8]. All but one of these individuals were very young children (7 years of age or less) when exposed 10 to 15 years before. All of the neoplasms were benign exceptfor a single carcinoma in a person exposed at age 30. As the latent period lengthened, carcinomas became numerous. The tmportance of the observations on the development of neoplasms in children is incidentally shown by an absence of any thyroid masses in 236 children and young adults rence of carcinoma. born after the accident and examined later by the Brookhaven Medical Team for inherited defects in the next generation [8]. Discussion ment of nodules had not been given during the first decade. Thyroid hormone prophylaxis against the possible develop- From the Marshallese experience it seems clear that a spectrum of thyroid neoplasms, including carcinoma, have resulted from wo : " a * b 7 "4 ft ey, eet suUTzZE Ss During the next decade, benign and later malignant neoplasms began to appear increasingly. The occurrence of lesions reached a peak at 25 years. Even after the peak had passed. 9