TY - JOUR T1 - Receptor Conversion in Invasive Breast Carcinoma Following Neoadjuvant Chemotherapy and Its Prognostic Significance A1 - Daniel Fischer A1 - Laura Meier A1 - Thomas Braun A1 - Stefan Koch A1 - Felix Roth JF - Asian Journal of Current Research in Clinical Cancer JO - Asian J Curr Res Clin Cancer SN - 3062-4444 Y1 - 2026 VL - 6 IS - 1 DO - 10.51847/NTSi1vjMGy SP - 172 EP - 185 N2 - Testing for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) is carried out on pre-neoadjuvant chemotherapy (NAC) core biopsies of invasive breast carcinoma (IBC). Yet, these assays are not standard practice on post-NAC IBC specimens that harbor residual malignancy. This research contributes to understanding how shifts in ER, PR, and HER2 expression between pre- and post-NAC IBC with persistent disease correlate with prognostic endpoints, namely disease-free survival (DFS) and overall survival (OS). The investigation followed a cohort framework, integrating both prospective and retrospective arms. Consequently, newly identified IBC patients who received surgical resection after NAC, whose pre-NAC biopsy material was accessible, and who had residual tumor within the breast, were recruited between January 2017 and January 2020 (n = 174) and observed longitudinally until July 2022. The analysis encompassed 174 subjects. Out of these 174, 77 (44%) cases initially classified as ER-positive switched to negative, 10 ER-positive cases retained positivity, and 87 (50%) cases originally ER-negative remained so. For PR, 48 (27%) PR-positive cases became negative, 10 PR-positive cases stayed positive, and 116 (67%) cases persisted as negative. Concerning HER2, 64 (36%) HER2-positive cases converted to negative, 4 (2%) HER2-positive cases maintained their positive status, and 103 (59%) cases remained negative. Individuals who transitioned from ER/HER2-positive to negative status achieved significantly longer DFS and OS. Discordance in hormone receptor (HR) and HER2 status occurs in IBC with residual disease following NAC, and subjects with post-NAC receptor profile changes have more favorable OS and DFS than those with stable receptor expression. UR - https://galaxypub.co/article/receptor-conversion-in-invasive-breast-carcinoma-following-neoadjuvant-chemotherapy-and-its-prognost-7t20bhkzvedekxd ER -