Clinicopathological Features and Disease Outcome in Breast Cancer Patients with Hormonal Receptor Discordance between Core Needle Biopsy and Following Surgical Sample

BACKGROUND: There are limited data about how to manage patients with discordant hormonal receptor (HR) status between core needle biopsy (CNB) and following surgical sample (FSS). This study aimed to evaluate clinicopathological features and disease outcome for these HR discordance patients. PATIENTS AND METHODS: Invasive breast cancer patients with paired HR between CNB and FSS were retrospectively analyzed, being classified into three groups: HR positive, HR negative, and HR discordance. Patient characteristics, treatment decisions, and disease outcome were compared among above groups. RESULTS: A total of 1710 patients (1233 HR positive, 417 HR negative, and 60 HR discordance patients) were enrolled. Compared with the HR positive group, HR discordance patients were associated with more human epidermal growth factor receptor 2 positivity (P < 0.001) and higher Ki67 level (P = 0.001) tumors. The fraction of patients receiving adjuvant chemotherapy was 95.0% and 93.8% in the HR discordance or HR negative groups, much higher than in the HR positive group (66.7%, P < 0.001). Of 60 HR discordance patients, 34 (56.7%) received adjuvant endocrine therapy. The 5-year disease-free survival (DFS) rate was 90.4% for HR discordant patients, showing no statistical difference compared with HR positive (87.0%, P = 0.653) or HR negative (83.2%, P = 0.522) groups. For HR discordance patients, there was no difference in DFS between patients who received adjuvant endocrine therapy or not (P = 0.259). CONCLUSIONS: HR discordance patients had similar tumor characteristics, adjuvant chemotherapy treatment, and DFS compared with HR negative patients. The benefit of endocrine therapy in these HR discordance patients is uncertain and deserves further clinical evaluation. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1245/s10434-019-07480-y) contains supplementary material, which is available to authorized users.