CDH1 and invasive lobular breast carcinoma: A great progress in the diagnosis of these lesions came with the observation that almost all cases of LN and invasive lobular carcinoma (ILC) lose the immunohistochemistry (IHC) signal for E-cadherin and β-catenin expression in the cytoplasm membrane, whereas the expression of these proteins is maintained in both in situ and invasive ductal carcinomas [3,12,13].