Epidemiological aspects of childhood cancer incidence in Czech regions

In this descriptive epidemiological report a total of 5100 childhood malignancies registered in Czech regions during the period of 1963-1985 was analyzed. The incidence of these tumors compared in years of this time period has been relatively constant, we did not find any significant changes in trends. That is why the average annual incidence rate, i.e., 10.8 in males and 8.7 in females per 100,000 sufficiently characterized the epidemiological situation in this respect. Those parameters allow, by knowledge of demographic prognosis, to estimate expected numbers of tumors in further years. The highest incidence occurred in boys and in the lower age groups of both sexes. All differences presented in this report were tested and were found to be significant. The percentage ratio of solid tumors, preferentially those of bone and skin of both sexes, and brain tumors in females in the period of 1976-1985, as compared to the period of 1961-1970, decreased, whereas there was a significant increase of systemic malignancies and soft-tissue sarcomas. Finally, the geographic differences of incidence are described, and the possible causes of the data presented are discussed.