Adolescents and young adults with cancers: comparative analyses of incidence and survival between Europe and the United States

Background: Epidemiological data on cancers in adolescents and young adults (AYAs; aged 15-39 years) suggest rising incidence of AYA cancers alongside international differences in incidence and survival. We compared incidence, survival and trends over time for cancers in AYAs in the European Union (EU) and the United States. Materials and methods: We used the EUROCARE-6 database and the US SEER program. We calculated crude incidence rates (IRs) over the years 2006-2013. We calculated 5-year relative survival (RS) in the follow-up period 2010-2014 using the period approach based on cases diagnosed in 2006-2013. We analysed IR and RS changes for the years 2000-2013. Results: Overall, 5-year RS was ∼84% in the EU and United States and improved over time in both regions. Compared with US patients, AYA cancer patients in the EU had lower survival for central nervous system (CNS) tumours and malignant melanoma but higher survival for leukaemias, testicular germ cell tumours (TGCTs), and cervical cancer. Both in the EU and the United States, major improvements in 5-year RS were observed for leukaemias, CNS tumours, lymphomas, and breast cancers. Cancer in AYAs corresponds to ∼5% of all new cancers diagnosed in the EU and United States. The IR increased for all cancers in AYAs in both regions, with the biggest increase due to thyroid cancers, TGCTs, and colorectal cancer. Conclusions: Our results show survival improvements for most types of AYA cancers and underline the need for further international efforts to increase survival for tumours (e.g. CNS tumours) for which 5-year RS remains <60%. Furthermore, the increasing incidence underscores the importance of giving priority to cancer prevention.