Predicting Effects of Clinicopathological Variables on Her2 Gene Amplification by Chromogenic in situ Hybridization (CISH) in IHC Her2 (2+) Breast Cancer Patients; A Study from Iran

Abstract

<span style="font-size: 14px;"><span style="font-family: times new roman;"><span style="text-align: justify;"><strong><span style="color: #0000ff;">Background & Objective:</span></strong></span></span></span><br /> <span style="font-size: 14px;"><span style="font-family: Times New Roman;">The <em>her2</em> amplification plays an important role in breast cancer management. Therefore, there is a need for using supplementary molecular methods in IHC equivocal cases. Present study has been conducted to determine the effects of clinicopathological variables on <em>her2</em> gene amplification by chromogenic in situ hybridization (CISH) in IHC Her2 (2+) breast cancer individuals.</span></span><br /> <span style="font-size: 14px;"><span style="font-family: times new roman;"><strong style="color: #0000ff; font-family: 'times new roman'; font-size: 14px;">Methods:</strong></span></span><br /> <span style="font-size: 14px;"><span style="font-family: Times New Roman;">A cross-sectional study was conducted in Zaferanyeh Laboratory collaborated with Shahid Beheshti University of Medical Sciences (Tehran-Iran; 2015-2018). All pathological data related invasive breast cancer patients with equivocal IHC results were included. CISH method was performed as a supplementary technique. The associations between histopathologic variables, status of Ki-67 index, progesterone and estrogen receptors (PR & ER) with her2 amplification by CISH were investigated and analyzed. The level of significance was considered as P-value < 0.05.</span></span><br /> <span style="font-size: 14px;"><span style="font-family: times new roman;"><strong style="font-family: 'times new roman'; font-size: 14px;"><span style="color: #0000ff;">Result:</span></strong></span></span><br /> <span style="font-size: 14px;"><span style="font-family: Times New Roman;">Totally, 239 patients with mean age of 53.2 years were studied. CISH identified <em>her2</em> gene amplification in 51 subjects (21.3%). The type of tumor (invasive ductal carcinoma), the tumor grade, and the value of Ki-67 index were directly correlated with her2 amplification. Significant negative associations were also observed between CISH results and ER and PR expression.</span><br /> <span style="font-family: times new roman;"><strong style="font-family: 'times new roman'; font-size: 14px;"><span style="color: #0000ff;">Conclusion:</span></strong></span><br /> <span style="font-family: Times New Roman;">As <em>her2</em> gene amplification was identified in 21.3% of invasive breast cancer patients with equivocal IHC results, it is supposed that applying CISH method may consider as a potentially valuable supplementary method. Results have also shown that higher grades of tumor, invasive ductal carcinoma, absences of hormone receptors and high Ki-67 index significantly correlated with the <em>her2</em> amplification. </span></span>