APC and cervical squamous intraepithelial neoplasia: Mutations in genes implicated in APC/β-catenin/Tcf pathway in CRC lacking APC mutations are also found in sporadic CIN tumors, in particular mutations of β-catenin in 48% of tumors without APC mutations [16], indicating that CTNNB1 mutations are present in the early stages of the colorectal pathogenesis and possibly substitutes the APC mutations in the stages of initiation [16,17].