Risk of neuroblastoma, maternal characteristics and perinatal exposures: The SETIL study.

Neuroblastoma (NB) is the most common extra-cranial paediatric solid tumour. Incidence peaks in infancy, suggesting a role of in-utero and neonatal exposures but its aetiology is largely unknown. The aim of the present study is to evaluate the association between maternal characteristics and perinatal factors with the risk of NB, using data from the SETIL database.SETIL is a large Italian population-based case-control study established to evaluate several potential cancer risk factors in 0-10 year olds. Information about maternal characteristics, reproductive history, environmental and occupational exposures during pregnancy, as well as newborns' characteristics were obtained using a structured questionnaire. Extremely low frequency magnetic field (ELF-MF) home exposure was measured. The study included 1044 healthy controls and 153 NB cases, diagnosed between 1998 and 2001.A twofold risk was associated to exposure in pregnancy to chemical products for domestic work and to hair dye. The risk associated with the latter was higher among 0-17 month old children (OR=5.5, 95\%CI: 1.0-29.3). Risk was increased for children whose mothers had suffered work related exposure in the preconception period to solvents (OR=2.0 95\%CI: 1.0-4.1) and in particular to aromatic hydrocarbons (OR=9.2, 95\%CI: 2.4-34.3). No association was observed with ELF-MF exposure. A higher risk was found among children with congenital malformations (OR=4.9, 95\%CI: 1.8-13.6) or neurofibromatosis (2 cases and 0 controls, p=0.016).Our study suggests maternal exposure to hair dyes and aromatic hydrocarbons plays a role and deserves further investigation. The association with congenital malformations might also be explained by over-diagnosis. External exposure, in particular during and before pregnancy might contribute to NB occurrence.