CDH1 and breast cancer: Lobular phenotypes of breast cancer in the carriers of pathogenic germline CDH1 variants can be confirmed by demonstration of p120-catenin staining in the cytoplasm; with negative staining for β-catenin; but there are no histopathological/immunohistochemical tests that can differentiate between lobular cancer which is associated with germline CDH1 variants and that associated with somatic variants in this gene [157].