Childhood cancer registrations in the developing world: Still more boys than girls

It has been shown previously that in many developing countries the reported incidence of childhood cancer for boys is substantially higher than for gi rls and that this difference is related to economic development of the coun try under study. The aim of the present study was to investigate the relati onship between the sex ratio of children registered with malignant diseases and national economic development. Sex ratios for childhood cancer registr ation were obtained for populations within 53 countries from the second vol ume of the International incidence of Childhood Cancer (range boys: girls 1 .09-2.05). Demographic, economic and health data for the corresponding coun tries were obtained from published statistics and used to determine the ext ent to which sex ratios were associated with national economic status. The ratio of boys:girls registered with childhood cancer increased with decreas ing gross domestic product and with increasing infant mortality, suggesting that boys are increasingly more likely than girls to be registered with in creasing economic disadvantage. Combining these results with childhood canc er registration data from northern England suggests that little of the pred ominance of boys reaching a specialist centre can be explained by differenc es between boys and girls in early deaths from the disease. The previously observed differences in the childhood cancer registration sex ratio in deve loping countries still exist. Hence, international differences in the incid ence of childhood cancer should be interpreted cautiously as they may not n ecessarily reflect only differences in the underlying occurrence of disease . (C) 2001 Wiley-Liss, Inc.