Childhood cancer mortality trends in Europe, 1990-2017, with focus on geographic differences

Aim: To monitor trends in childhood cancer mortality in Europe. Methods: We calculated age-standardized mortality rates per 100,000 children (age 0-14 years) from 1990 to the last available calendar year, for all neoplasms and six main cancers in childhood, in selected European countries and geographic areas, plus the European Union (EU), using data from the World Health Organization database. We carried out a joinpoint regression analysis of mortality trends for all neoplasms, leukaemia and tumours of the nervous system.Results of the joinpoint regression were summarized through annual percent change (APC) for each identified linear segment, and weighted average APC (AAPC) over the whole period. Results: From 1990 to 2015, childhood total cancer mortality rates dropped by 2.8% per year in the EU, to reach 2.6/100,000 in the latest available calendar years. The greatest declines were in central-eastern countries (AAPCs -3% to -4%). Recent rates ranged between 1.7 and 4.3 deaths/100,000, with the highest values in central-eastern Europe. Leukaemia mortality rates in the EU decreased from 1.6 to 0.6/100,000 in the latest calendar years (AAPC -4%). The deepest declines were registered in central-eastern countries, though they still showed the highest rates (0.9). The lowest leukaemia mortality rates were in northern-western Europe (0.5/100,000), but also in the Czech Republic and Poland. Southern European countries showed comparatively high rates (0.8). Nervous system tumours showed relatively modest falls (AAPC: -1.7% in the EU). Conclusions: Childhood cancer mortality continued to decline steady in Europe, though geographic differences persist. Further efforts are required to fill the gap, by promoting widespread and rational adoption of currently available treatment protocols.