Because the association between CDH1 pathogenic variants and BC has been questioned and E-cadherin expression has been associated with LBC, the present study examines the proportion of large CDH1 rearrangements in probands with BC predisposition that are negative for pathogenic variants in the BRCA1 and BRCA2 genes. This evidence concerns the gene CDH1 and CDH1-related diffuse gastric and lobular breast cancer syndrome.