At definitive histology, a G3, ER-negative, PgR-negative, Ki67 = 90%, c-erb-2 negative invasive ductal carcinoma was diagnosed with free tumor margins; each specimen of the medial, lateral, and deep edges of the 4th external intercostal muscle was free from neoplastic infiltration, as well. Here, PGR is linked to invasive ductal breast carcinoma.