The feasibility of using liquid biopsies as a complementary assay for copy number aberration profiling in routinely collected paediatric cancer patient samples

•Overall, concordance between copy number aberrations in tissue and plasma is good.•Discordance was associated with low-quality cfDNA samples and localised disease.•Copy number aberrations can be unique to either tissue DNA or tumour DNA.•No false-positives or false-negatives were seen for MYCN detection in neuroblastoma cases.