Department of Pathology, Shenzhen Affiliated Hospital, Guangzhou University of Traditional Chinese Medicine, Shenzhen, China.
Histopathology. 2011 Aug;59(2):264-73. doi: 10.1111/j.1365-2559.2011.03921.x.
Epidermal growth factor receptor (EGFR) is frequently expressed in basal-like breast cancer (BLBC). The aim of this study was to evaluate their correlation as detected by immunohistochemistry (IHC) or fluorescence in-situ hybridization (FISH).
IHC for oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor (HER) 2, cytokeratin (CK) 5/6 and EGFR, and FISH for EGFR amplification, were performed in 59 cases of BLBC. EGFR IHC results were scored semiquantitatively, and compared with its gene amplification status. ER, PR and HER2 were negative in all cases, whereas 35 and 55 cases were positive for CK5/6 and EGFR. For EGFR IHC, 20, 11, 11 and 17 cases showed a negative, a low, an intermediate or a high staining level, respectively, and seven cases showed gene amplification by FISH, with two, 19, 11 and 20 cases showing balanced monosony, disomy, trisomy, and polysomy respectively. Immunohistochemical expression in gene-amplified tumours was significantly higher than in those without amplification, including balanced polysomy tumours. EGFR immunohistochemical expression also correlated with the EGFR/chromosome 7 ratio. High sensitivity (86%) and negative predictive value (98%) were achieved with high-level immunohistochemical expression as a cut-off to predict gene amplification.
High-level EGFR immunohistochemical expression correlated with and predicted EGFR amplification, and may be used as a screening method to exclude gene amplification.
表皮生长因子受体（EGFR）在基底样乳腺癌（BLBC）中常表达。本研究旨在通过免疫组化（IHC）或荧光原位杂交（FISH）评估其相关性。
对 59 例 BLBC 进行了雌激素受体（ER）、孕激素受体（PR）、人表皮生长因子受体 2（HER2）、细胞角蛋白（CK）5/6 和 EGFR 的 IHC 及 EGFR 扩增的 FISH 检测。EGFR IHC 结果进行半定量评分，并与基因扩增状态进行比较。所有病例 ER、PR 和 HER2 均为阴性，CK5/6 和 EGFR 阳性分别为 35 例和 55 例。EGFR IHC 显示阴性、低、中、高染色水平的分别为 20、11、11 和 17 例，FISH 显示基因扩增的有 7 例，分别为平衡单体、二倍体、三倍体和多倍体 2、19、11 和 20 例。基因扩增肿瘤的免疫组化表达明显高于无扩增肿瘤，包括平衡多倍体肿瘤。EGFR 免疫组化表达与 EGFR/7 号染色体比值相关。高水平免疫组化表达作为预测基因扩增的截定点，具有较高的灵敏度（86%）和阴性预测值（98%）。
高水平 EGFR 免疫组化表达与 EGFR 扩增相关，并可作为一种筛选方法排除基因扩增。
