Significant advancements in childhood cancer treatment have led to increased survival rates, prompting research into long-term effects. Educational attainment is a crucial factor for future opportunities, and childhood cancer survivors may face challenges due to treatment-related absences, disease impact, or treatment-induced cognitive deficits. Previous studies have shown lower educational attainment among central nervous system (CNS) tumor survivors and those receiving CNS-directed therapy. However, findings for other cancer types are inconsistent, with reports of similar, worse, or better outcomes compared to peers. Methodological limitations, such as reliance on self-reported data, selection bias due to non-participation, limited follow-up, and single-timepoint assessments, hinder definitive conclusions. This study aims to address these limitations using a large, population-based, register-based cohort study spanning Denmark, Finland, and Sweden to examine upper secondary education attainment in young adulthood. This study further aims to identify vulnerable survivor subgroups and assess educational delays.

Existing literature reveals inconsistent findings on the educational attainment of childhood cancer survivors. Studies consistently demonstrate lower educational attainment in survivors of CNS tumors and those treated with CNS-directed therapy. However, research on survivors of other cancer types presents conflicting results, reporting outcomes comparable to, worse than, or even better than their peers. Methodological limitations in many previous studies, including the use of self-reported outcomes, selection bias due to non-participation, limited follow-up time, and assessment of educational attainment at a single point in time, contribute to the inconclusive nature of the findings. The existing literature does not definitively clarify whether survivors experience only delays in educational attainment or whether they continue to lag behind their peers in adulthood. This study leverages the unique opportunity offered by comprehensive population-based registries from Denmark, Finland, and Sweden to address these critical gaps in knowledge.

This register-based matched cohort study utilized data from national cancer registries and population registries in Denmark, Finland, and Sweden. The study population included long-term survivors of childhood cancer (diagnosed ages 0–14 years between 1971 and 2005, alive and not emigrated by age 25). For each survivor, five population comparisons were randomly selected and matched by sex, year of birth, and country of residence. Siblings (aged within 5 years of the survivor) formed a second comparison group. Individuals with Down syndrome, neurofibromatosis, or tuberous sclerosis were excluded. The primary outcome was upper secondary education attainment by age 25, with secondary outcomes including attainment without delay and attainment of tertiary education. Covariates included age at diagnosis, parental education level, hospital time spent around diagnosis, and hospital contacts (somatic and psychiatric) in early adulthood. Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for not attaining upper secondary education by age 25, comparing survivors to both population comparisons and siblings. Stratified analyses were conducted to explore potential effect modifiers.

The study included 7629 survivors, 35,411 population comparisons, and 6114 siblings. 80.3% of survivors attained upper secondary education by age 25, compared to 84.4% of population comparisons and 84.0% of siblings. The adjusted odds ratio (OR) for not attaining upper secondary education by age 25 was 1.32 (95% CI: 1.23–1.40) when comparing survivors to population comparisons and 1.57 (95% CI: 1.40–1.77) when comparing survivors to siblings. The association varied significantly by cancer type. Survivors of CNS tumors showed the strongest association (OR_{surv vs PopComp} = 2.05, 95% CI: 1.83–2.29; OR_{Surv vs Sib} = 2.72, 95% CI: 2.19–3.39), while the association was less pronounced for ALL. Survivors of other leukemias, lymphomas, and non-CNS solid tumors had similar educational attainment to population comparisons. Stratified analyses revealed that longer hospital stays and early adulthood hospital contacts, particularly psychiatric contacts, increased the risk of not attaining upper secondary education. Parental education significantly impacted attainment, with the largest difference between survivors and comparison groups observed among those with highly educated parents. Survivors were less likely to complete upper secondary education without delay (71.3% vs 77.2% of population comparisons and 77.7% of siblings). A smaller proportion of survivors attained tertiary education by age 30, but this difference was smaller when restricted to those who had completed upper secondary education by age 25.

This large, population-based study demonstrates that while many childhood cancer survivors experience delays in upper secondary education, many catch up by age 25. The exception is CNS tumor survivors, who consistently show a significant disadvantage, corroborating previous research. The findings for ALL survivors suggest a potential influence of cranial radiotherapy used in earlier treatment periods. The increased risk associated with longer hospital stays and early adulthood hospital contacts (especially psychiatric) underscores the importance of comprehensive post-treatment care. The interaction between parental education and cancer survivorship highlights the complex interplay of socioeconomic factors and health outcomes. The study strengthens the existing evidence regarding the late effects of childhood cancer on educational trajectories, providing further refinement by cancer type and by factors that can influence outcomes. This study is unique in its use of multiple comparison groups (population comparisons and siblings) and its large, multi-country population-based approach. These aspects of the study mitigate potential bias. However, the lack of detailed treatment information is a limitation.

This study confirms that while many childhood cancer survivors experience educational delays, most achieve upper secondary education by age 25. Survivors of CNS tumors represent a vulnerable group requiring targeted support. Hospitalization duration and early adulthood hospital contacts, particularly psychiatric issues, predict educational difficulties. Future research should incorporate detailed treatment information to better understand the underlying mechanisms and identify at-risk individuals for timely intervention.

The study's limitations include a lack of information on specific reasons for educational delays and the absence of detailed treatment data, particularly cranial radiation therapy. While the large sample size and multiple comparison groups are strengths, generalizability might be limited by the specific healthcare and educational systems of the three Nordic countries studied. The study's findings pertain to survivors diagnosed over a long period during which treatment protocols varied. Therefore, the results may not apply to current treatment paradigms, which highlights the need for ongoing monitoring of educational outcomes among more recently treated survivors.