In the case of our patient with intraductal carcinoma and a single lymph-node micrometastasis identified on the extemporaneous cryo-cut section, we chose to analyse HER2 copy-number-variation on laser-microdissected cells because, for HER2, the level of gene amplification is correlated to protein overexpression [1]. Here, ERBB2 is linked to ductal breast carcinoma in situ.