A component of lobular carcinoma in clinically lymph node-negative patients predicts for an increased likelihood of upstaging to pathologic stage III breast cancer

In this cohort, patients with a component of lobular carcinoma were more often surgically upstaged to pathologic stage IIIA or higher, which is a classical indication for postmastectomy radiation therapy. Our findings suggest that ILC is often more extensive than it appears clinically and has significant implications for management of patients with lobular carcinoma after the discovery of a positive SLN.