Central nervous system tumours among adolescents and young adults (15-39 years) in Southern and Eastern Europe: Registration improvements reveal higher incidence rates compared to the US.

•Malignant central nervous system tumours incidence in adolescents and young adults in Southern and Eastern Europe was higher compared to the US.•Variable temporal trends were recorded mainly attributed to the improvement of cancer registration.•Astrocytomas comprised half of malignant central nervous system tumours in both regions.•A male preponderance and an increasing incidence with age were similarly recorded in both regions.•The high proportion of unspecified cases necessitates the optimisation of cancer registration in Southern and Eastern Europe.