Non-Hodgkin lymphoma has increased significantly over the past 50 years, although it has began to stabilize among adults. To understand the rise in children, adolescents and young adults, this study looked at possible causes, using a Swedish large-scale study (3.5 million people). Key factors were:
- utero conditions and genetics contributed to the incidence of NHL, with family history of NHL in either a sibling or parent being the strongest association
- older maternal age
- low birth order
- high fetal growth
In children under 15 years of age:
- male gender was found to be linked with NHL incidence, but not with later onset of NHL.