Abstract
BACKGROUND: Down syndrome (DS) is a common genetic disorder resulting from an extra copy of genetic material from all or part of chromosome 21. Individuals with DS have a higher burden of co-occurring structural birth defects, neurocognitive delay, and chronic health conditions when compared to those without DS, as well as a 10 to 20-fold excess risk for acute leukemia (AL). Few studies have reported the late effects of cancer treatment in DS-AL survivors, and even fewer have compared outcomes to children with DS and no cancer history. The Children’s Oncology Group study ALTE22C1 was developed to address this knowledge gap. METHODS: This study leverages both registry and site-based DS-AL survivor recruitment and a prospective/retrospective cohort design to compare chronic health conditions and neurocognitive outcomes experienced by DS-AL survivors to age and sex-matched individuals enrolled to a DS cohort for which cancer is exclusionary. Survivors 6–39 years old, ≥ 3 years from end of AL treatment, and in remission are eligible. Participants complete a medical conditions survey and neuropsychological battery by parent proxy and may also participate in an in-person physical and neurocognitive assessment. Biological samples are collected to evaluate molecular features associated with outcomes. DISCUSSION: This cooperative group study will identify the prevalence and severity of medical and neurocognitive outcomes in DS-AL survivors compared with non-DS AL and DS controls without cancer history. Results are anticipated to inform clinical practice guidelines for DS-AL survivors and improve survivor outcomes through mitigation of outcome disparities in this vulnerable population. TRIAL REGISTRATION: Children’s Oncology Group study ALTE22C1 is registered under the ClinicalTrials.gov identifier NCT05702645.