50-year-old female underwent excision of a not-movable, hard tumor in her breast.
- Intraductal proliferations of monomorphic rounded cells, some of which exhibit distinct nucleoli. A papillary, micropapillary and a cribriform growth pattern and comedo necroses are observed (DCIS) within ducts.
- In between the distended ducts with the intraductal carcinoma an ill-defined tumor is present that infiltrates and destroys the surrounding tissue.
- Some of the tumor cells grow in well-formed glands, some in small solid aggregates (invasive ductal carcinoma, NOS).
- The tumor cells stain intensely with the pan-cytokeratin antibody Lu-5, corresponding to their epithelial origin.