HER2 (++) Amplification in Breast Cancer Detected by Fluorescence in Situ Hybridization and Its Correlation with Clinicopathological Features

Abstract

Objective To detect the amplification of HER2 gene by fluorescence in situ hybridization(FISH), and explore the correlation between HER2 gene amplification and clinicopathological characteristics. Methods We collected 325 cases of breast cancer with HER2(++) in the Affiliated Tumor Hospital of Xinjiang Medical University from January 2013 to December 2015. All paraffin-embedded specimens were detected by IHC and FISH respectively for the expression of HER2 protein and amplification. And we analyzed the relationship between HER2 gene amplification and clinicopathological characteristics of patients. Results HER2(++) of all groups was detected immunohistochemically. And the amplification rate of HER2 gene was 12.9%(42/325). Univariate analysis on 12 clinicopathological indexes showed that the amplification status of HER2 gene was significantly correlated with hormonal status, tumor diameter and P53, rather than ki67 expression, histological grade, tumor number or other factors. Conclusion The negative expression of estrogen and progesterone, tumor diameter > 2 cm and positive P53 expression are the independent factors to predict IHC HER2(++) amplification by FISH.

Keywords

• breast cancer
• hormone receptor
• her2
• immunohistochemistry
• fluorescence in situ hybridization(fish)