Germline mutations and new copy number variants among 40 pediatric cancer patients suspected for genetic predisposition.

Cancer predisposition syndromes (CPS) result from germline pathogenic variants, and they are increasingly recognized in the etiology of many pediatric cancers. Herein, we report the genetic/genomic analysis of 40 pediatric patients enrolled from 2016 to 2018. Our diagnostic workflow was successful in 50% of screened cases. Overall, the proportion of CPS in our case series is 10.9% (20/184) of enrolled patients. Interestingly, 12.5% of patients achieved a conclusive diagnosis through the analysis of chromosomal imbalance. Indeed, we observed germline microdeletions/duplications of regions encompassing cancer-related genes in 50% of patients undergoing array-CGH: EIF3H duplication in a patient with infantile desmoplastic astrocytoma and low-grade Glioma; SLFN11 deletion, SOX4 duplication, and PARK2 partial deletion in three neuroblastoma patients; a PTPRD partial deletion in a child diagnosed with glioblastoma multiforme. Finally, we identified two cases due to DICER1 germline mutations.