To investigate myoepithelial MMP13 expression in the context of β6 positive DCIS, a previously established marker of high-risk DCIS24, 30 human breast samples, comprising 10 normal breast tissue, 10 DCIS and 10 IDC were analysed for expression of MMP13 by RNAscope. This evidence concerns the gene MMP13 and ductal breast carcinoma in situ.