Female patients with different breast lesions including benign proliferating lesions, ductal carcinoma in-situ (DCIS), and invasive carcinoma breast cases were included in the study. Inflammatory lesions, mesenchymal, and metastatic tumors were excluded. IHC expression of DOG1 as a myoepithelial marker to discriminate invasive from non-invasive breast lesions was evaluated and correlated with clinicopathological features. The gene discussed is ANO1; the disease is ductal breast carcinoma in situ.