Report summary

Cancer is rare during childhood, adolescence and young adulthood. Successive national cancer strategies have recommended that cancer among this age group should be managed in an age-appropriate environment by professionals with expertise both in the cancers that occur at this age and in the holistic care of children and teenagers and young adults (TYA) respectively. As a result, childhood and TYA cancer care has become increasingly specialised and successive periods have witnessed improvements in survival outcomes.

However, despite some notable successes in improving survival, cancer remains the most common cause of childhood death outside of infancy, and the most common disease-related cause of death in teenagers and young adults (TYAs): only accidents and suicide are responsible for more deaths in this age group.

For many years, UK-wide data on the incidence and survival of childhood cancer (ages 0- 14 years) were reported by the University of Oxford's National Registry of Childhood Tumours, and subsequently TYA cancer data (15-24 years) were collated and reported by the North West Cancer Intelligence Service. There have been no detailed UK-wide reports of cancer incidence, survival or mortality since 2012, and there has never been a report that combined the analysis of data throughout the child-TYA age spectrum, despite many cancers typical of this age affecting both children and TYA. The absence of contemporary UK-wide data and the siloed nature of age-specific analyses limited to children and TYA are recognised to be unhelpful in understanding UK-wide progress in the management of these rare cancers.

Therefore, the four UK national cancer registries have come together to describe for the first time the incidence, survival and mortality from cancer diagnosed among children, teenagers and young adults resident in the United Kingdom, based on data from the National Cancer Registration and Analysis Service for England (Public Health England), the Northern Ireland Cancer Registry, the Scottish Cancer Registry, and the Welsh Cancer Intelligence and Surveillance Unit.

Our analysis relates to children and young people who were diagnosed with cancer under the age of 25 during the 20-year period of 1997-2016. The UK cancer registries use data provided by patients that is collected by the health service as part of their care and support. Cancer occurrence and outcomes in children and in TYAs are already included in reports by population-based cancer registries of the United Kingdom. However, there are several reasons why a special analysis is needed.

• The classification of tumours used for adults is principally based on their anatomical site, while it is the cell type that is more important in classifying cancers in children and TYA. The International Classification of Childhood Cancer, third edition (ICCC-3) is a more meaningful alternative and has been used in this report.
• Cancers in children and young people are relatively uncommon but as a result it can be difficult to draw inferences from small numbers in individual cancer registries. It is therefore an advantage to bring together data from all countries that comprise the United Kingdom to provide more precise results.

While cancer is rare in young people there were around 75,000 young persons diagnosed with cancer over the twenty years of this study, approximately 3,755 per year. There were around 33,000 cases diagnosed in children (0-14 year olds), an average of 1,645 cases per year, and 42,000 cases for TYAs (15-24 year olds), 2,110 per year.

Among children aged 0-14 years at diagnosis, leukaemia accounted for 31% of registrations, central nervous system (CNS) and miscellaneous intracranial and intraspinal neoplasms for 25%, lymphomas for 10%, soft-tissue sarcomas for 6%, neuroblastoma and other peripheral nervous cell tumours for 6%, and renal tumours for 6%.

 Among TYA aged 15-24 years at diagnosis, carcinomas (other than renal, hepatic and gonadal) and malignant melanomas accounted for 30% of registrations, lymphomas for 20%, germ cell, trophoblastic and gonadal tumours for 16%, CNS and miscellaneous intracranial and intraspinal neoplasms for 12%, leukaemia for 9%, and soft-tissue sarcomas for 5%. No other diagnostic groups accounted for more than 5% of registrations in the respective age ranges.

Among young people aged 15-24 malignant melanoma was twice as frequent in females as it was in males. Melanoma accounted for 10% of all cancer registrations in this age group, and skin carcinomas for a further 5%. Both of these cancer types are highly amenable to primary prevention, and health improvement interventions to reduce exposure to ultraviolet light and particularly to avoid sunburn and use of sunbeds1 could potentially prevent around 15% of all cancers in young people aged 15-24. Cervical carcinoma accounted for 6% of cancers in females aged 15-24 and is largely preventable through vaccination against human papillomavirus.

Overall, five-year survival increased from 77% for children under 15 years of age who were diagnosed in 1997-2001 to 84% for those diagnosed in 2012-2016. Five-year survival for TYA aged 15-24 years increased from 79% to 87% between the same two periods.

Survival also increased over the study period for many categories of cancer, including lymphoid leukaemia, acute myeloid leukaemia, chronic myeloid leukaemia, chronic myeloproliferative diseases, myelodysplastic syndrome (in children), Hodgkin lymphoma, non-Hodgkin lymphomas, astrocytoma, other and mixed gliomas, brain stem glioma (in children), meningioma (in TYA), neuroblastoma (in children), osteosarcoma, Ewing sarcoma family of tumours (in TYA), rhabdomyosarcoma, CNS germinoma (in TYA), breast carcinoma (in TYA) and malignant melanoma (in TYA).

Some categories which already had an excellent prognosis with five-year survival exceeding 90% during the study period, with little room for further improvement; include pilocytic astrocytoma, pituitary adenoma and carcinoma, craniopharyngioma, retinoblastoma, nephroblastoma (Wilms tumour), gonadal germ-cell tumours, thyroid carcinoma and skin carcinoma.

The trend of survival increase was not uniform across the entire period, and there are several cancers with poorer prognosis which there has been little evidence of improvement in the most recent periods, notably ependymoma, medulloblastoma, hepatoblastoma, Ewing sarcoma in children and colorectal carcinomas in TYAs. TYAs continued to have worse survival than children for osteosarcoma, Ewing sarcoma and rhabdomyosarcoma, without any recent improvement. However, while TYA survival remains worse than childhood survival for acute lymphoid and myeloid leukaemia and non-Hodgkin lymphomas, the gap has reduced over time.

Cancer in children, teenagers and young adults accounts for 0.3% of all cancer deaths in the UK. In 2018 there were around 260 childhood cancer deaths, accounting for 7% of all childhood deaths (0-14 year olds). For teenagers and young adults (15-24 year olds) there were nearly 290 cancer deaths, accounting for 11% of all TYA deaths. For comparison, cancer accounts for almost 30% of all deaths in the whole UK population.

This report provides detailed baseline data on cancer incidence and survival among children and TYA in the four UK nations over the 20-year period 1997-2016. In addition to providing updated statistics, future work might include analysis of trends in incidence rates and research into the reasons for any variations in incidence and survival between the four nations.

Notes:

1 T.R. Fears, J. Scotto, M.A. Schneiderman. Mathematical models of age and ultraviolet effects on the incidence of skin cancer among whites in the United States. Am. J. Epidemiol., 105 (5) (1977), pp. 420-427

Prepared by:

Catherine Welham, Charles Stiller, Lucy Irvine, Luke Hounsome and Martin McCabe at the National Cancer Registration and Analysis Service for England (Public Health England).

Anna Gavin and David Donnelly at the Northern Ireland Cancer Registry.

David Morrison, Amy McKeon, Lesley Bhatti, Mhairi Maclennan and Mor Kandlik Eltanani at the Scottish Cancer Registry.

Dyfed Huws, Giles Greene, Janet Warlow, Lloyd Evans and Rebecca Thomas at the Welsh Cancer Registry.

Thanks to the members of the PHE CTYA Expert Advisory Group, Dr Angela Jesudason and Dr Cathy Morley-Jacob and patient representatives for their helpful input during preparation of the report.