The study, published in the scientific journal European Journal of Cancer, shows that the incidence of cancer in children up to 17 years of age has increased by an average of 0.6% per year. Whereas in the 1990s around 480 children per year were diagnosed with cancer, in 2010-2017 the number was more than 540 a year. This increase was especially noticeable among 0-year-olds and 10-17-year-olds. Ardine Reedijk used data from the Netherlands Cancer Registry (NKR) for the study, which she conducted with Leontien Kremer, Rob Pieters and Henrike Karim-Kos among others.
Forms of cancer
A number of cancers accounted for the slight increase in new cases. Leukemia rose particularly in the 1990s and does not seem to have increased any further since 2000. Some 150 new cases of leukemia are currently diagnosed every year. Brain tumors, neuroblastomas and Ewing bone tumors show a more even rise. Melanomas showed an increase until 2002, after which there now seems to be a decline again. Other cancers remained stable over time. The results are comparable to those in other European countries.
In general, there are various causes that can explain such an increase: improved diagnostics, better registration or an actual increase. This study shows that improved diagnostics have led to improved staging of Hodgkin lymphomas, soft tissue tumors and thyroid tumors. Germ cell tumors of the testicles and melanomas were also diagnosed more often at an earlier stage. However, this did not lead to a huge increase in the number of new cases. This means that the improved diagnostics cannot account for the overall increase in the number of new cases of cancer in children.
The influence of changes in registration has been minimized by the researchers by disregarding those cancers that were not fully registered in the past in their analyses. It is therefore possible that this is a real increase in the number of cases. However, there is still too much unknown about factors that increase the risk of cancer in children to be able to give a satisfactory answer.
Conclusion and further research
Between 1990 and 2017 there was a slight increase in the number of children with cancer in the Netherlands. This increase is visible in some forms of childhood cancer, the cause of which is unknown. The researchers argue that it is important to continue this research in the future and, in addition to research into new methods of treatment, to also conduct research at the Princess Máxima Center into the risk factors of cancer in children.