The mutation and abnormality of AXIN2 (Axis inhibition protein 2) can lead to the occurrence of ampullary carcinoma (Hayata et al., 2021), endometrial cancer (Syed et al., 2020), and liver cancer (Abitbol et al., 2018) by adjusting the stability of beta-catenin. The gene discussed is CTNNB1; the disease is carcinoma of the ampulla of vater.