LAUSR

BACKGROUND This study investigated patients with invasive lobular breast carcinoma (ILC) to determine the benefit of neoadjuvant systemic therapy (NAST). METHODS Patients with ILC treated from 2006 to 2015 were identified. Tumor characteristics and treatment data were analyzed. RESULTS Of the 560 patients with ILC, 77 patients received NAST. Patients who received NAST presented with larger clinical T stages compared to patients who received surgery first (p < 0.001). Pathological complete response (pCR) to NAST was seen in 17% of patients. Only 14% of patients with clinically positive lymph nodes downstaged to N0. These patients were more likely to have HER2 positive tumors (p < 0.029) and larger tumor size at diagnosis (p < 0.015). Mastectomy was performed in 84% of patients and lumpectomy in 16%. CONCLUSIONS Only a minority of patients with ILC achieve pCR. The majority of patients still undergo mastectomy; therefore the benefit of NAST in ILC appears limited.