The first ever global estimates of undiagnosed childhood cancer suggest the true number of new paediatric cancer cases each year could be double than that currently recorded.
Previous estimates for the total incidence of global childhood cancer have been based on data from cancer registries. However, registries identify cases in defined populations. Furthermore, 60 per cent of countries worldwide do not have national cancer registries and of those that do, some only cover a small fraction of the overall population.
This latest model, the Global Childhood Cancer microsimulation model, incorporates data from cancer registries in countries where they exist, combined with data from the World Health Organization’s Global Health Observatory, demographic health surveys and household surveys developed by UNICEF.
In the findings, published in the Lancet Oncology, the model estimates that in 2015, there were 397,000 childhood cancer cases globally, compared with 224,000 recorded diagnoses. This suggests almost 44 per cent (173,000 cases) of global childhood cancer cases were undiagnosed. There was substantial regional variation, ranging from 3 per cent in both Western Europe (120 undiagnosed cases out of 4,300 total new cases) and North America (300 of 10,900 cases) to 57 per cent (43,000 of 76,000 new cases) in Western Africa.