Syntaxin-1 and Insulinoma-Associated Protein 1 Expression in Breast Neoplasms with Neuroendocrine Features

• DOI: 10.3389/pore.2021.1610039
• Publication Date: 2021-10-26T04:11:12Z
• Authors: Sándor Turkevi-Nagy; Ágnes Báthori; János Böcz; László Krenács; Gábor Cserni; Bence Kővári
• Keywords: Chromogranin A; Synaptophysin; Neuroendocrine differentiation

Introduction: A subset of breast neoplasia is characterized by features neuroendocrine differentiation. Positivity for Neuroendocrine markers immunohistochemistry required the diagnosis. Sensitivity and specificity currently used are limited; based on definitions WHO Classification Tumours, 5th edition, about 50% tumors with differentiation express chromogranin-A 16% synaptophysin. We assessed applicability two novel markers, syntaxin-1 insulinoma-associated protein 1 (INSM1) in carcinomas. Methods: Hypercellular (Type B) mucinous carcinomas, solid papillary invasive carcinomas no special type ductal situ subtype were included our study. The immunohistochemical panel chromogranin A, synaptophysin, CD56, INSM1. INSM1 was determined using samples negative synaptophysin CD56. Results: sensitivity 84.7% (50/59), diffuse positivity more than 60% cases. Syntaxin-1 also had an excellent (98.1%). Depending definition positivity, 89.8% (53/59) or 86.4% (51/59), its being 57.4% 88.9%. sensitivities CD56 98.3, 74.6 22.4%, respectively. Discussion: sensitive specific features, outperforming recommend to be routine panel.