We identified 18 pathologically confirmed fresh frozen invasive lobular breast carcinomas of classical histology with heterogeneous E-cadherin expression (EcadhetILC), of which 11 were amenable to microdissection to separate out E-cadherin negative (Neg) and aberrant/positive components (Abr), where aberrant E-cadherin protein expression was defined as weak or cytoplasmic staining [9]. The gene discussed is CDH1; the disease is invasive lobular breast carcinoma.