ERBB2 and breast cancer: The rate of occult NAC involvement reported in patients with invasive BC, is highly variable (from 0% to 27%) [31, 32, 18, 33] and mammographic distance between tumor and nipple, axial tumor-NAC distance at magnetic resonance imaging [31, 32], tumor size, pathologic staging [34, 35] and HER2 amplification [33] have been proposed to predict NAC status.