265P - Oncologic outcome of invasive lobular carcinoma: Is it different from that of invasive ductal carcinoma?

Abstract

BackgroundTo evaluate the clinicopathological factors and the oncology outcomes of invasive lobular carcinoma (ILC) patients compared with those of invasive ductal carcinoma (IDC) patients. MethodsThis study was a medical record review based on a prospectively-collected database. We surveyed the clinicopathological characteristics and oncology survival between IDC and ILC following curative surgery at ooo Medical Center between March 2007 and February 2015. ResultsThe median follow-up time was 60.5 months (range: 3-121 months). There were 352 breast cancer patients with ILC and 7795 breast cancer patients with IDC. There were 13 breast cancer patients with ILC and 1150 breast cancer patients with IDC in the TNBC patients. The IDC patients had 77.7% of cytokeratin (CK) 5/6 and 86.3% of Epidermal growth factor receptor (EGFR), while ILC patients only had 15.4% of CK5/6 and 23.1% of EGFR. In TNBC, patients with ILC showed a tendency to have a worse prognosis than patients with IDC. However, there was no statistical difference in disease-free survival (DFS, p=0.122) or overall survival (OS, p=0.093) between TNBC patients with IDC and with ILC. ConclusionsPatients with ILC have no different oncologic outcome than patients with IDC. However, patients with ILC in TNBC show a tendency to have a worse prognosis than patients with IDC in TNBC. This result may be related to CK5/6 and EGFR. Further research is needed with larger sample sizes. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.