Incidence and survival of children and young people with central nervous system embryonal tumours in the North of England, 1990-2013

Background: Medulloblastoma and primitive neuroectodermal tumours (PNET) are the most common central nervous system (CNS) embryonal tumours diagnosed in childhood. Survival outcomes are worse for children diagnosed with CNS PNET compared to medulloblastoma. Less is known about survival outcomes in teenagers and young adults (TYA). Methods: Data were extracted from two population-based cancer registries of children and young people (0-24 years) in the north of England for all diagnoses of medulloblastoma and CNS PNET between 1990 and 2013. Incidence and survival trends were analysed using Poisson and Cox regression. Results: Between 1990 and 2013, 197 medulloblastomas and 58 CNS PNET were diagnosed; age standardised incidence rates of 3.8 and 1.5 per million, respectively. Medulloblastoma incidence decreased over time while there was no significant change in trend for CNS PNET. The overall 5 year survival rate was 54%. The risk of death was 2.4 times higher (95%CI 1.6, 3.7) for patients with CNS PNET compared to medulloblastoma, after adjustment for patient characteristics. There was a 39% reduction (95%CI 0.43, 0.87) in the risk of death for patients diagnosed between 2000 and 2013 compared to 1990-1999. Risk of death did not differ for TYA (15-24 years) compared to children aged 5-9 years. Conclusions: Medulloblastoma incidence decreased over time and differences in survival between medulloblastoma and PNET emerged within the first year post diagnosis leading to poorer outcomes for children and young adults diagnosed with PNET, however a significant improvement in survival over time was observed.