Thyroid cancer in Belarus: the epidemiological situation

Starting in 1990, an increasing number of children were diagnosed as suffering from thyroid cancer in regions close to the Chernobyl nuclear accident site, and this increase is continuing. But still today, doubts about the significance of this increase are being voiced. Using data from the Belarus epidemiological cancer registration system up to 1994, the geographic distribution, time and cohort trends, age distribution and other characteristics of this epidemic are reviewed. Results show that the geographic distribution is similar to that of iodine-131 following the accident; that when looking at cohorts of children born in the same years incidence has steadily increased since 1990; and that deviations from this pattern might be explained by active case finding.The most likely interpretation of these results is that of a causal association with radiation exposure related to the Chernobyl accident, but possible modifying factors should be examined closely. The most likely future course of the epidemic is an increasing number of cases among those exposed in childhood, and public health measures should take this into account