KRT5 and breast carcinoma: Although CK5/6 and EGFR are noticeably associated with breast cancer invasiveness and cell proliferation, tumors with CK5/6 and EGFR positivity characteristically have several mitotic figures, scant stromal content, and frequent apoptotic cells and show apparent central necrosis and the stromal lymphocytic response (15), which may lead to most of the changes in the DCE-MRI perfusion parameters being less obvious.