Purpose: To study the mortality due to leukaemia during childhood and youth in Spain in the period 1951-1985.
Material and methods: The mortality for all types of leukaemia in that period was studied in three aspects: (a) By reviewing the rates of specific mortality for ages under 20 years, at quinquennial intervals and per millions of inhabitants of those ages. (b) Studying the mortality per cohorts of births at five-year intervals from 1951-1955 to 1981-1985. (c) Attaining the statistical value, "observed deceased" of leukaemia in people under 15 years of age for the period studied and on each year of that period, and comparing such value with the number of "expected deceased", with regard to the reference year, 1965.
Results: A decreasing trend was observed along the whole period. As for ages, there seems to be some tendency to stabilisation of the mortality in the last five-year period, 1981-1985 (there is a decrease only in the 15-18 age-group). These data were confirmed when assessing the mortality per "birth cohorts" or generations, and after plotting the figures of "observed" and "expected" mortality in accordance with the previous evolution.
Conclusion: It was inferred that regard to the mortality of childhood and youth leukaemia, in Spain the situation has improved markedly, doubtless as a result of better therapeutical approach. This evolution closely resembles the patterns of the most developed countries from a sanitary standpoint.