Kumarasinghe Marian Priyanthi, de Boer Willem Bastiaan, Khor Tze Sheng, Ooi Esther M, Jene Nic, Jayasinghe Sureshini, Fox Stephen B
1PathWest Laboratory Medicine, Perth 2School of Pathology and Laboratory Medicine, University of Western Australia, Perth 3School of Medicine and Pharmacology, Royal Perth Hospital Unit, University of Western Australia, Perth, WA 4Department of Pathology, Peter MacCallum Cancer Centre, East Melbourne 5Department of Pathology and Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Vic, Australia.
Pathology. 2014 Apr;46(3):184-7. doi: 10.1097/PAT.0000000000000075.
The aim of this study was to compare HER2 amplification, as determined by the HER2 copy number (CN) and the HER2/CEP17 ratio, with protein expression in gastric and gastro-oesophageal junction (G/GOJ) adenocarcinoma.HER2 immunohistochemistry (IHC) and silver in situ hybridisation (SISH) were performed in 185 cases. Modified gastric criteria were used for IHC scoring. HER2 and CEP17 CNs were counted in at least 20 cancer cells and the ratio calculated as per previously defined protocols. These two SISH methods were statistically compared against the different IHC scores.Thirty-four cases showed amplification, by both methods in 29, and either method in five. IHC score was 3+ in 29 cases; 26 showed amplification by both methods, one by ratio only and two were not amplified. IHC score was 2+ in 24 cases; three showed amplification by both methods and two by either. One each of IHC 1+ and 0 showed an increased ratio but not CN. The HER2 CN and ratio for IHC score 3+ compared to scores 2+, 1+ and 0 were significantly different (all p < 0.01). The CN for IHC 2+ vs IHC 1+ and IHC 0 was significantly different (both p < 0.01) but the ratio was not (p = 0.5711 and p = 0.2857, respectively). The CN and the ratio for scores 1+ and 0 were not significantly different (p = 0.9823 and p = 0.9910, respectively).The HER2 CN differentiates between the different IHC scores better than the HER2:CEP17 ratio. Cases that show IHC3+ and high CN may not require calculation of the ratio. Furthermore, consideration should be given to the CN when IHC negative cases appear amplified by the ratio only.
本研究旨在比较通过HER2拷贝数（CN）和HER2/CEP17比值测定的HER2扩增情况与胃及胃食管交界（G/GOJ）腺癌中的蛋白表达。对185例病例进行了HER2免疫组织化学（IHC）和银原位杂交（SISH）检测。IHC评分采用改良的胃标准。在至少20个癌细胞中计数HER2和CEP17 CN，并按照先前定义的方案计算比值。将这两种SISH方法与不同的IHC评分进行统计学比较。34例显示扩增，两种方法均显示扩增的有29例，仅一种方法显示扩增的有5例。IHC评分为3+的有29例；26例两种方法均显示扩增，1例仅比值显示扩增，2例未扩增。IHC评分为2+的有24例；3例两种方法均显示扩增，2例仅一种方法显示扩增。IHC 1+和0各有1例显示比值升高但CN未升高。IHC评分为3+与2+、1+和0相比，HER2 CN和比值有显著差异（均p<0.01）。IHC 2+与IHC 1+和IHC 0相比，CN有显著差异（均p<0.01），但比值无显著差异（分别为p=0.5711和p=0.2857）。1+和0评分的CN和比值无显著差异（分别为p=0.9823和p=0.9910）。HER2 CN比HER2:CEP17比值能更好地区分不同的IHC评分。显示IHC3+和高CN的病例可能无需计算比值。此外，当IHC阴性病例仅比值显示扩增时，应考虑CN情况。
