Prevalence and severity of chronic diseases in adult survivors of childhood cancer: A report from the Childhood Cancer Survivor Study

9 Background: Survivors of childhood cancer experience a variety of chronic diseases, defined as physical late effects with a potential for serious disability. This analysis was conducted to determine the incidence of chronic diseases in adult survivors of childhood cancer and determine the relative risk compared to sibling controls. Methods: The Childhood Cancer Survivor Study is a retrospective cohort study tracking health outcomes of long-term survivors (> 5 years) who were diagnosed 1970–1986 and a comparison group of siblings. The incidence of chronic diseases occurring in adult (≥ 18 years of age) survivors (N=10397) and siblings (N=3034) were calculated. A severity score, using the Common Terminology Criteria for Adverse Events, v3.0 (grades 1–4), were assigned to each chronic disease. For example, grade 4 diseases included: second malignant neoplasm (excluding non-melanoma skin and thyroid cancer), myocardial infarction or coronary artery bypass surgery, heart transplant, dialysis or kidney transp...