Epidermal growth factor receptor expression and gene amplification in colorectal carcinoma: an immunohistochemical and chromogenic in situ hybridization study.

摘要: Recent data suggest that detection of epidermal growth factor receptor protein by immunohistochemistry (IHC) does not predict response to the antiepidermal drug, cetuximab, in patients with colorectal carcinoma. In searching for foundation further investigation optimize patient selection cetuximab therapy, this study sought exploit tissue microarray and chromogenic situ hybridization techniques evaluate status gene amplification cancer its relationship expression IHC. The included 158 primary or metastatic adenocarcinomas. Immunohistochemical results were scored as 0–3+ based on intensity membrane staining. signals counted 30 nuclei per core. Overall, rate loss was 7%, yielding 147 analyzable cases: 123 primary, 24 metastatic. Positive immunohistochemical staining any detected 85% (105/123) 79% (19/24) tumors, whereas (>5 copies/nucleus) only seen 12% (15/123) 8% (2/24) tumors. Only 2/15 1/2 tumors showed amplified at a high level (>10 copies/nucleus). Although positive correlation between likelihood both (P=0.01) (P=0.05) IHC had low specificity (17% 23% metastatic) predicting amplification. Conversely, all did express lacked Thus, shows small fraction receptor- carcinomas are associated Additional studies needed determine whether bears informative value cetuximab-based therapy.