Survival of European adolescents and young adults diagnosed with cancer in 2010-2014

Background: We used the comprehensive definition of AYA (age 15 to 39 years) to update 5 -year relative survival (RS) estimates for AYAs in Europe and across countries and to evaluate improvements in survival over time. Methods: We used data from EUROCARE-6. We analysed 700,000 AYAs with cancer diagnosed in 2000 -2013 (follow-up to 2014). We focused the analyses on the 12 most common cancers in AYA. We used period analysis to estimate 5 -year RS in Europe and 5 -year RS differences in 29 countries (2010 -2014 period estimate) and over time (2004 -06 vs. 2010 -14 period estimates). Findings: 5 -year RS for all AYA tumours was 84%, ranging from 70% to 90% for most of the 12 tumours analysed. The exceptions were acute lymphoblastic leukaemia, acute myeloid leukaemia, and central nervous system tumours, presenting survival of 59%, 61%, and 62%, respectively. Differences in survival were observed among European countries for all cancers, except thyroid cancers and ovarian germ -cell tumours. Survival improved over time for most cancers in the 15- to 39 -year -old age group, but for fewer cancers in adolescents and 20- to 29year -olds. Interpretation: This is the most comprehensive study to report the survival of 12 cancers in AYAs in 29 European countries. We showed variability in survival among countries most likely due to differences in stage at diagnosis, access to treatment, and lack of referral to expert centres. Survival has improved especially for haematological cancers. Further efforts are needed to improve survival for other cancers as well, especially in adolescents.