Risk Factors of Subsequent Central Nervous System Tumors after Childhood and Adolescent Cancers: Findings from the French Childhood Cancer Survivor Study

Background: Childhood or adolescent cancer survivors are at increased risks of subsequent primary neoplasms (SPN) of the central nervous system (CNS) after cranial irradiation. In a large multicentric cohort, we investigated clinical and therapeutic factors associated with the long-term risk of CNS SPN, and quantified the dose-response relationships. Methods: We selected all CNS SPN cases diagnosed up to 2016 among members of the French Childhood Cancer Survivor Study at least 5 years after first cancer diagnosis in 1946-2000. Four controls per case were randomly selected within the cohort and matched by sex, year of/age at first cancer diagnosis, and follow-up time. On the basis of medical and radiological reports, cumulative radiation doses received to the SPN or matched location were retrospectively estimated using mathematical phantoms. We computed conditional logistic regression models. Results: Meningioma risk significantly increased with higher radiation doses [excess OR per Gy (EOR/Gy) = 1377; P < 0.001; 86 cases; median latency time = 30 years), after adjustment for reported genetic syndromes and first CNS tumor. It was higher among youngest individuals at first cancer diagnosis, but did not vary with follow-up time. On the opposite, radiation-related glioma risk (EOR/Gy = 0.049; P = 0.11; 47 cases; median latency time = 17 years) decreased over time (P for time effect = 0.05). There was a significant association between meningioma risk and cumulative doses of alkylating agents, but no association with growth hormone therapy. Conclusions: The surveillance of patients with cranial irradiation should continue beyond 30 years after treatment. Impact The identified risk factors may inform long-term surveillance strategies.

Automated summary

Childhood or adolescent cancer survivors undergoing cranial irradiation are at increased risk of developing subsequent primary neoplasms of the central nervous system (CNS), particularly meningiomas, and the risk is significantly associated with radiation dose. Monitoring patients with cranial irradiation should continue for at least 30 years post-treatment to ensure early detection and intervention. Identified risk factors, such as radiation dose and cumulative alkylating agents, can help inform long-term surveillance strategies for this population.