tripple negative ductal invasive carcinoma of breast is ?

MEDULLARY CARCINOMA breast : * High nuclear grade, aneuploidy, hormone receptors - nt, HER2/neu overexpression -nt. * Lymph node metastases -infrequent. * Syncytial growth pattern and pushing borders - d/t overexpression of adhesion molecules -> intercellular cell adhesion molecule and E-cadherin -) limit metastatic potential. HISTOLOGY : Solid, syncytium-like sheets of large cells with vesicular, pleomorphic nuclei, prominent nucleoli 4 > 75% of the tumor Frequent mitotic figures; Moderate to marked lymphoplasmacytic infiltrate surrounding and within the tumor. Pushing (noninfiltrative) border. * Poorly differentiated. ref : bailey and love 27th ed