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Background: High-dose ionizing radiation is an established risk factor for childhood central nervous system tumors (CNST) but the role of low doses remains debated. In particular, there are few studies of natural background radiation (NBR, gamma radiation and radon) and childhood CNST, and their results are inconclusive., Objectives: This study aimed to investigate the ecological association between NBR exposure and childhood CNST incidence in France, considering childhood CNST overall and by subgroups., Methods: Incidence data were provided by the French national registry of childhood cancers, which has high completeness. We included 5471 childhood CNST cases registered over the period 2000-2012, and their municipality of residence at diagnosis was recorded. Municipality NBR exposures were estimated by cokriging models, using NBR measurements and additional geographic data. The incidence rate ratio (IRR) per unit variation of exposure was estimated with Poisson regression models. NBR exposures were considered at the time of diagnosis, and cumulatively from birth to diagnosis. In an exploratory analysis, the total brain dose due to NBR was used., Results: Overall, there was no association between NBR exposure and childhood CNST incidence (IRR = 1.03 (0.98,1.09) per 50 nSv/h for gamma radiation, and IRR = 1.02 (0,96,1.07) per 100 Bq/m 3 for radon). An association was suggested between pilocytic astrocytomas and gamma radiation (IRR = 1.12 (1.00,1.24) per 50 nSv/h) but not with radon (IRR = 1.07 (0.95,1.20) per 100 Bq/m 3 ). Upward trends for this CNST subtype were also suggested with the cumulative exposures to gamma radiation and the total brain dose. NBR exposure was not associated with other CNST subgroups (ependymomas, embryonal tumors, and gliomas other than pilocytic astrocytomas). Adjustment for socio-demographic factors did not change the findings., Conclusions: Our study was based on high quality incidence data, large numbers of CNST cases, and validated models of NBR exposure assessment. Results suggest an association between gamma radiation, as a component of NBR, and pilocytic astrocytomas incidence in France., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Solid tumors are uncommon in the neonatal period but represent an important cause of mortality and morbidity., Procedure: Using the French National Registry of Childhood Solid Tumors database, all children, from birth to 28 days of age inclusive, with a primary malignant solid tumor diagnosed between 2000 and 2009 in mainland France were identified. Tumors were classified according to the third version of the International Classification of Childhood Cancer., Results: Of total 285 solid tumors over 10 years, the most common cancer was neuroblastoma (47%), followed by germ cell tumors (29%), central nervous system tumors (10%), and soft tissue sarcomas (8%). The annual incidence was 36.6 per million live births. No statistically significant change in time trends of incidence was observed during 2000-2009. Routine ultrasonography during pregnancy established the diagnosis in 52% of cases. Thirteen neonates (4.5%) had congenital abnormalities associated with their tumors. For all solid tumors combined, overall survival was 84.2% (95% CI, 79.4-87.9) at 1 year and 83.8% (95% CI, 79.0-87.6) at 5 years. More favorable prognosis was significantly associated with neonates treated by surgery (65% of cases) compared to those without tumor excision. However, perioperative and postoperative mortality was 8%., Conclusions: Because of their relative rarity, there is a paucity of objective information on the epidemiology, optimal treatment, and long-term outcome of neonatal solid tumors. But to obtain a clearer picture of the epidemiology of neonatal tumors, it is essential to have some recommendations on the methodological approach used to study them., (© 2016 Wiley Periodicals, Inc.)

Background: Central nervous system (CNS) tumors are the second most common childhood malignancy. The French National Registry of Childhood Solid Tumors (NRCST) makes it possible to describe this variety of distinct tumor types and to provide incidence and survival data in France on a nationwide basis., Methods: All children aged 0-14 years, who were registered with a primary CNS tumor in the NRCST of France between 2000 and 2008, were identified. Tumors were classified according to the International Classification of Childhood Cancer, third edition., Results: Approximately 57% of pediatric CNS tumors were gliomas, with astrocytomas of the pilocytic type predominating. Distributions of subtypes by age showed that primitive neuroectodermal tumors and ependymomas mainly occurred in children aged <5 years. The mean annual incidence rate of CNS tumors was 39 per million. No statistically significant change in time trends of incidence rate was observed during 2000-2008. For all tumors combined, overall survival was 84.8% (95% CI, 83.7%-85.9%) at 1 year and 72.9% (95% CI, 71.5%-74.3%) at 5 years. Survival time trends were studied in a multivariate analysis observing a reduction in the risk of death in periods of diagnosis 2003-2005 (HR = 0.8; 95% CI, 0.7–0.9) and 2006-2008 (HR = 0.7; 95% CI, 0.6-0.9) compared with 2000-2002., Conclusions: The stable incidence rates during the last 10 years could indicate that major changes in environmental risk factors are unlikely, but the ongoing need for population-based surveillance remains relevant. Results indicate a positive trend in the survival probability still persistent in the 2000s.