OCCULT THYROID CARCINOMAS IN THE REGION OF MINSK, BYELARUS - AN AUTOPSY OF 215 PATIENTS

Thyroid glands from 215 patients, aged 19 to 88 years, without known t hyroid disease, were serially sectioned at 2-3 mm intervals and micros copically examined for occult disease. Glands were normal in 32.5%, wh ile nodules were observed in 60% and adenomas in 13%. Carcinomas were found in 20 cases (9.3%): occult papillary carcinomas in 19 (8.8%) and one medullary carcinoma. No carcinomas were found in the thyroids of 15 patients less than 40 years of age. There were no significant diffe rences in frequency of occult carcinomas between female and male patie nts and, for patients over 40 years, with increasing age. Of the 19 pa pillary tumours more than one focus was found in six cases (a total of 28 foci). The diameter of 27 of these tumours was less than or equal to 5 mm (96.4%), with one exception (diameter 6.3 mm). These findings were compared with those obtained in 86 thyroid glands of children sur gically resected for carcinomas between 1986 and 1991. Only 10 of thes e tumours (11.6%) were less than or equal to 1 cm. These tumours, howe ver, were significantly larger than the occult papillary carcinomas an d their morphological features were quite different. Our results are d iscussed with regard to the possible role of factors other than irradi ation due to the nuclear accident at Chernobyl, and the observed sharp numerical increase of thyroid carcinomas in children of the Republic of Belarus after this event.