Abstract
To the Editor: The recent report of Favus et al. (N Engl J Med 294:1019–1025, 1976) sheds much light on the nature of the "epidemic" of radiation induced-thyroid carcinoma in the Chicago area. Forty-nine of their 60 cases are "occult" thyroid carcinoma (less than 1.5 cm), 15 of which are less than 1 mm. These are harmless tumors that are extremely common if careful methods are used for their detection. The prevalence of 33 per cent in the pathologically studied thyroid glands reported by Favus et al. is higher than that in American autopsy series,1 , 2 but nearly the same . . .