Research Paper Volume 11, Issue 22 pp 10052—10060

Late stage gastric cancer patients with extra gained HER2 positivity by dual block assessment may not show compromised efficacy to trastuzumab treatment

Chen Xu 1, *, , Yalan Liu 1, *, , Dongxian Jiang 1, , Xiaowen Ge 1, , Jie Huang 1, , Jieakesu Su 1, , Xue Zhang 1, , Shaohua Lu 1, , Yuan Ji 1, , Jun Hou 1, , Tianshu Liu 2, , Yingyong Hou 1, ,

  • 1 Department of Pathology, Zhongshan Hospital, Fudan University, Shanghai, China
  • 2 Department of Oncology, Zhongshan Hospital, Fudan University, Shanghai, China
* Equal contribution

received: May 19, 2019 ; accepted: October 28, 2019 ; published: November 17, 2019 ;

https://doi.org/10.18632/aging.102415
How to Cite

Copyright © 2019 Xu et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

Dual block HER2 assessment can effectively increase the HER2 positive rate in resected specimens of gastric cancer (GC). The aim of this study is to explore whether GC patients with extra gained HER2 positivity by dual block assessment can benefit from trastuzumab therapy. Twenty-eight GC patients receiving gastrectomy prior to trastuzumab treatment were retrospectively analyzed. All the cases routinely accepted dual block HER2 assessment. The cases were divided into 2 cohorts based on HER2 status: cohort A with concordant HER2 results and cohort B with discordant HER2 results between the two blocks (cases with extra gained HER2 positivity). Response rate (RR), progress free survival (PFS) and overall survival (OS) were compared between the two cohorts. The results showed that no significant differences were found between the two cohorts in main clinicopathologic characteristics. No statistical difference was found in response rate (47.6% vs 57.1%) (P=1.0), either. The two cohorts did not demonstrate statistical differences in the PFS (10.5 months (95%CI 6.4-14.6) vs 8.0 months (95%CI 3.2-12.8), P=0.686) and the OS (23.3 months (95%CI 12.1-34.5) vs 20.0 months (95%CI 10.1-29.9), P=0.776). In conclusion, our study suggests that patients with extra gained HER2 positivity may not show compromised efficacy to trastuzumab treatment.

Abbreviations

GC: Gastric cancer; HER2: human epidermal growth receptor 2; IHC: immunohistochemistry; FISH: fluorescence in situ hybridization; PFS: progression free survival; OS: overall survival; RR: response rate; CR: complete response; PR: partial response; SD: stable disease; PD: progressive disease.