Sornmayura Pattana, Rerkamnuaychoke Budsaba, Jinawath Artit, Euanorasetr Chakrapan
Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
J Med Assoc Thai. 2012 Jan;95(1):88-95.
To determine human epidermal growth-factor receptor 2 (HER2) protein-overexpression frequency and the concordance rate between immunohistochemistry and fluorescence in situ hybridization techniques in gastric carcinoma.
A retrospective analysis of gastric adenocarcinomas obtained from 224 adult patients between January 2000 and December 2008 were performed. The paraffin-embedded tissues were sliced into 4-microm-thick sections and analyzed for HER2 protein expression levels by immunohistochemistry (IHC) using an automated slide-staining IHC system. Breast carcinoma tissues were included in every staining batch as positive control. In order to detect and quantify amplification of the HER2, the authors performed fluorescence in situ hybridization (FISH) using PathVysion HER2 DNA Probe Kit. The IHC results were independently recorded by two pathologists using the standard HER2 scoring system for gastric carcinoma. FISH results were interpreted using standard guideline as employed in breast carcinoma. The two-tailed-Fisher's exact test was used to assess the concordance between IHC and FISH results.
HER2 protein overexpression level was identified in 9% (20 in 224 cases) of the gastric tumors; 80% of which were well or moderately differentiated and of the intestinal or mixed type. However HER2-overexpressing tumors comprised only 16% of the intestinal/mixed-type or well/moderately differentiated tumors. There was no signal obtained from 29 specimens from FISH studies. Thus, the overall results of IHC and FISH methods were concordant in 88% (171 out of 195, p < 0.001).
There is a significant concordance rate between IHC and FISH in gastric carcinoma. The present study is the first HER2 study of such carcinoma in Thai patients.
确定胃癌中人类表皮生长因子受体2（HER2）蛋白过表达频率以及免疫组织化学与荧光原位杂交技术之间的符合率。
对2000年1月至2008年12月期间224例成年患者的胃腺癌进行回顾性分析。将石蜡包埋组织切成4微米厚的切片，使用自动玻片染色免疫组织化学系统通过免疫组织化学（IHC）分析HER2蛋白表达水平。每次染色批次均包括乳腺癌组织作为阳性对照。为了检测和定量HER2的扩增，作者使用PathVysion HER2 DNA探针试剂盒进行荧光原位杂交（FISH）。两位病理学家使用胃癌的标准HER2评分系统独立记录IHC结果。FISH结果按照乳腺癌中采用的标准指南进行解读。采用双尾Fisher精确检验评估IHC和FISH结果之间的符合率。
在9%（224例中的20例）的胃肿瘤中鉴定出HER2蛋白过表达；其中80%为高分化或中分化，且为肠型或混合型。然而，HER2过表达肿瘤仅占肠型/混合型或高分化/中分化肿瘤的16%。FISH研究的29个标本未获得信号。因此，IHC和FISH方法的总体结果在88%（195例中的171例，p<0.001）中是一致的。
胃癌中IHC和FISH之间存在显著的符合率。本研究是泰国患者中此类癌症的首个HER2研究。
