Cohort Profile: The Swiss Childhood Cancer Survivor Study

Thanks to continuous improvements in therapy, 5-year survival of childhood cancer in developed countries now exceeds 80%, leading to a growing population of long-term survivors. As the cancer and treatment can cause adverse effects long after the illness has been cured, assessment of long-term quality of life (QOL), somatic, psychological and social outcomes become increasingly important. Although cancer in children is rare, the population impact of late toxicities on disability-adjusted life years is considerable because of the young age at diagnosis. Up to now, many single-centre studies or clinical trials have been published, but only few large representative long-term follow-up studies exist, including the Childhood Cancer Survivor Studies in the USA (CCSS), Canada and Great Britain (BCCSS). These studies found increased risks of second malignant neoplasms (SMNs), mortality and chronic medical problems such as endocrine dysfunctions, cardiovascular problems, stroke or infertility. Psychosocial problems such as depression, anxiety and post-traumatic symptoms have also been reported. Life-long medical follow-up is thus recommended for high-risk patients. For these reasons, we created a national cohort study of all survivors of childhood and adolescent cancer in Switzerland, the Swiss Childhood Cancer Survivor Study (SCCSS).