Clinical Significance of HER2 Overexpression in Gastric and Gastroesophageal Junction Cancers.

Abstract

BACKGROUND:

In this study, we investigated the rate of human epidermal growth factor receptor 2 (HER2) overexpression in gastric (GC) and gastroesophageal junction cancers (GEJCs) and the relationship with HER2 expression and clinical, pathological parameters and prognosis.

METHODS:

Surgery or biopsy specimen of 598 (436 males, 162 females) patients with GC or GEJC was evaluated for the presence of HER2 overexpression by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) methods.

RESULTS:

HER2 IHC scores were as follows: 418 (69.9%) IHC 0, 58 (9.7%) IHC 1+, 50 (8.4%) IHC 2+, 72 (12%) IHC 3+. Among 50 patients with IHC 2+, 18 (38.2%) were FISH positive, and 29 (61.7%) were FISH negative for HER2 amplification. Patients were regarded as HER2 positive in case of IHC 3+ disease or IHC 2+ disease with a positive FISH test result for HER2 amplification. In the primary analysis population, 90 (15%) were considered HER2 positive. HER2 positivity was higher in intestinal GC compared to diffuse GC (16.9 vs 6.6%, p = 0.014). HER2 positivity was significantly higher in well and moderately differentiated tumors than poorly differentiated tumors (p < 0.0001). HER2 positivity had no significant effect on median OS (23.2 vs 19.1 months, p = 0.44). But in the early stages (stages I and II), median OS of HER2-positive patients was shorter than HER2-negative patients (51.4 months vs not reach, p = 0.047). However, median OS was similar in patients with advanced stages (stages III and IV) HER2-positive and HER2-negative disease (16.2 vs 13.7 months, p = 0.72).

CONCLUSIONS:

Rate of HER2 positivity is similar in Turkish patients with GC and GEJCs. HER2 positivity is associated with poor prognosis in patients with early-stage disease.

• Authors: Meltem Baykara, Mustafa Benekli, Ozgur Ekinci, Sultan Cigdem Irkkan, Halit Karaca, Umut Demirci, Muhammed Bulent Akinci, Olcun Umit Unal, Faysal Dane, Fatma Paksoy Turkoz, Ozan Balakan, Eylem Pinar Eser, Selcuk Cemil Ozturk, Metin Ozkan, Berna Oksuzoglu, Alper Sevinc, Necla Demir, Hakan Harputluoglu, Bulent Yalcin, Ugur Coskun, Aytug Uner, Ahmet Ozet, Suleyman Buyukberber, Anatolian Society of Medical Oncology (ASMO)
• Journal: Journal of gastrointestinal surgery : official journal of the Society for Surgery of the Alimentary Tract (J Gastrointest Surg) Vol. 19 Issue 9 Pg. 1565-71 (Sep 2015) ISSN: 1873-4626 [Electronic] United States
• PMID: 26179664 (Publication Type: Journal Article)

Chemical References

• ERBB2 protein, human
• Receptor, ErbB-2

Topics

• Adult
• Aged
• Aged, 80 and over
• Esophagogastric Junction
• Female
• Gene Expression
• Humans
• Immunohistochemistry
• In Situ Hybridization, Fluorescence
• Male
• Middle Aged
• Neoplasm Grading
• Neoplasm Staging
• Prognosis
• Receptor, ErbB-2 (genetics, metabolism)
• Stomach Neoplasms (genetics, metabolism, pathology)
• Survival Rate
• Young Adult