title: Significance of accurate human epidermal growth factor receptor-2 (HER2) evaluation as a new biomarker in gastric cancer.
abstract: BACKGROUND
  HER2 testing in gastric cancer differs from testing in breast cancer because of inherent differences in tumor biology; gastric cancer more frequently shows HER2 heterogeneity and incomplete membrane staining. The aim of the present study was to evaluate the frequency and accuracy of detection of HER2 expression by application of standard criteria in Japanese patients with gastric cancer.
  
  
  METHODS
  A total of 198 tumor specimens were assessed for HER2 expression by immunohistochemistry (IHC) using the antibodies HercepTest™ and 4B5. Both hand-operated and automated IHC were performed.
  
  
  RESULTS
  HER2 expression differed according to the IHC method and antibodies used. HER2 IHC3+ tumors were identified in 21 (10%) and 7 (3.5%) cases by hand-operated and automated IHC, respectively.
  
  
  CONCLUSIONS
  Among patients with gastric cancer, FISH may be performed in cases of IHC1+ by automated IHC. Further research is required to clarify the relevance of HER2 staining and scoring for the clinical response to HER2-targeted therapy.
authors: Department of Gastroenterological Surgery, National Kyushu Medical Center, Clinical Research Institute, Fukuoka, Japan Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan yasuek@surg2.med.kyushu-u.ac.jp.
authors: Yasue
authors: Y
authors: Kimura
authors: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Eiji
authors: E
authors: Oki
authors: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Ayae
authors: A
authors: Yoshida
authors: Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Shinichi
authors: S
authors: Aishima
authors: Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Yoko
authors: Y
authors: Zaitsu
authors: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Hajime
authors: H
authors: Ohtsu
authors: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Koji
authors: K
authors: Ando
authors: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Satoshi
authors: S
authors: Ida
authors: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Hiroshi
authors: H
authors: Saeki
authors: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Masaru
authors: M
authors: Morita
authors: Department of Gastroenterological Surgery, National Kyushu Medical Center, Clinical Research Institute, Fukuoka, Japan Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Tetsuya
authors: T
authors: Kusumoto
authors: Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Yoshinao
authors: Y
authors: Oda
authors: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Yoshihiko
authors: Y
authors: Maehara
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis* / Q000037:antagonists & inhibitors; D013274:Stomach Neoplasms / Q000737:chemistry* / Q000473:pathology / Q000628:therapy
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human
keywords: Human epidermal growth factor receptor-2 (HER2); gastric cancer; immunohistochemistry (IHC)