P-093 - HER2 protein over-expression in early stage gastric cancer: correlation with clinicopathological features and survival

Date 04 July 2015
Event WorldGI 2015
Session Posters
Topics Biomarkers
Gastric Cancer
Pathology/Molecular Biology
Presenter T. Yavuzsen
Citation Annals of Oncology (2015) 26 (suppl_4): 1-100. 10.1093/annonc/mdv233
Authors T. Yavuzsen1, N. Demir1, U. Oflazoglu1, N. Kazaz1, I. Somali1, T. Unek2, O. Sagol1, S. Sarioglu1, K. Atila1, I. Oztop1
  • 1Dokuz Eylül University Faculty of Medicine, İzmir/TR
  • 2Department of Medical Oncology, Izmir/TR

Abstract

Introduction

In ToGA study established standard scoring criteria of human epidermal growth factor receptor 2 (HER2) for gastric cancer and demonstrated the efficacy of trastuzumab for treating metastatic gastric cancer. The aim of the present study was to evaluate the frequency of HER2-positive cases with resectable gastric cancer and to examine the relationships between HER2 expression and prognosis and clinicopathological features.

Methods

A total of 120 patients with surgical gastric carcinoma, stage I-III were included in this retrospective study. Tumor samples were examined for HER2 expression by immunohistochemistry (IHC) and some cases both IHC and HER2 amplification by in situ hybridization.

Results

HER2-positive tumors were identified in 26 patients (21%). Six patients with IHC score of 0/1 positive, and 7 patients with IHC score 2 positive, HER2 over-expression was detected by in situ hybridization. There was significantly positive association between HER2 overexpression and tumor differentiation, WHO classification and Lauren classification. On the contrary, no association was found between HER2 over-expression and sex, smoking, tumor location, stage, lymphovascular/venous/perineural invasion. There was not any significant difference between HER'-positive and –negative patients in terms of disease free survival and median overall survival.

Conclusion

Though there was significantly positive association between HER2 expression status and tumor differentiation, histological type, it may be of limited prognostic value in early gastric cancer patients.