E-cadherin is typically negative in normal and neoplastic lobular cells
It appears to be a sensitive marker of ductal differentiation vs lobular differentiation; but its utility in borderline lesions is currently uncertain
In pagetoid spread of LCIS or ALH into ducts, an E-caherin negative population will be seen disrupting the positively stained normal ductal cells
Cytokeratin 8 (detected by CAM5.2) may stain both ductal and lobular processes but accentuates the discohesive pattern in LCIS and ALH ("bag of marbles")
