Figure 1
From: Diagnostic evaluation of papillary lesions of the breast on core biopsy
(ai–ii) Benign papilloma (H&E). (aiii) Dual CK5/6 (red) and P63 (brown) immunohistochemical staining of benign papilloma. The continuous myoepithelial cell layer shows positive nuclear stating for P63 and cytoplasmic CK5/6 staining (thin arrow). In addition, hyperplastic epithelial cells show a mosaic pattern of cytoplasmic CK5/6 positivity (thick arrow). (b) Atypical papilloma. (bi) H&E. (bii) P63 and CK5/6. The area with atypical histological features (thin arrow) shows loss of epithelial CK5/6 staining compared with the non-atypical area (thick arrow). (c) Papillary carcinoma. (ci) H&E. (cii) P63 and CK5/6. Complete absence of P63 and CK5/6 staining indicates absence of the myoepithelial cell layer. Epithelial CK5/6 staining is also absent. (d) Core biopsy of papillary lesion. (di) Broad sclerotic fibrovascular cores on H&E (arrow). (dii) Positive CK5/6 staining of epithelial cells (arrow). Scale bars=100 μm.
