APC and Crohn disease: Colorectal carcinomas are classified by etiology as inherited (e.g., hereditary nonpolyposis colorectal cancer due to genetic instability and familial adenomatous polyposis (FAP) coli due to a mutation in the adenomatous polyposis coli gene, APC), inflammatory (e.g., Crohn’s disease and ulcerative colitis), or sporadic [2].