Long-term survivors of childhood central nervous system malignancies: the experience of the Childhood Cancer Survivor Study

In the last four decades, advances in neurosurgical technique, delivery of radiation therapy (RT), supportive care, and use of chemotherapy have improved 5-year survival for children with central nervous system (CNS) malignancies. Currently, in the United States 74% of children will become 5-year survivors of their primary CNS malignancy. This improved outcome has resulted in a new and growing population of childhood cancer survivors. Surgery, RT and chemotherapy, while essential components of primary treatment for most childhood CNS malignancies, have also been associated with risk of long-term morbidity and late mortality. The Childhood Cancer Survivor Study, a retrospective cohort of over 14,000 survivors of childhood cancer diagnosed between 1970 and 1986, has been an important resource for quantification of associations between these therapeutic modalities and risk of long-term adverse health and quality of life outcomes. CNS malignancy survivors are at significant risk for late mortality, development of second neoplasms, as well as increased risk for multiple endocrinopathies and adverse neurologic health conditions. Importantly, the CCSS has identified a number of dose-response relationships between RT and development of subsequent malignant neoplasms of the central nervous system, abnormal timing of menarche and neurocognitive function. Ongoing study of childhood cancer survivors is needed to establish long-term risks and evaluate impact of newer techniques such as conformal RT or proton beam delivery that limit RT exposure and may reduce long-term effects.