Several studies observing different cohorts of BWS patients confirmed higher tumor risk associated with the H19/IGF2:IG-DMR hypermethylated and UPD(11)pat subgroup and high frequency for Wilms tumor and hepatoblastoma (Maas et al., 2016; Ounap, 2016; Brioude et al., 2018; Kamien et al., 2018; MacFarland et al., 2018; Wang et al., 2020). This evidence concerns the gene IGF2 and hepatoblastoma.