Abstract:

Objective

To investigate the usage of nuclei and tissue microarrays technique in detecting HER-2 gene amplification and protein expression in breast carcinoma.

Methods

Two hundred and forty-eight breast carcinoma paraffin embedded tissue blocks were used to construct tissue microarray groups.Fluorescence in situ hybridization (FISH)and immunohistochemistry (IHC) were used to detect the expressions of HER-2 gene and protein.The detection results of the two methods were analyzed using Kappa test.Taking the results obtained from FISH analysis as the gold standard, the ROC curve of IHC detecting HER-2 expression was drawn.

Results

The Kappa test of the two methods showed an acceptable consistency (Kappa=0.711,P=0.000).The area under the ROC curve of IHC detecting HER-2 expression was 0.888 (P=0.000), the Youden's index was 0.700 and an accuracy was 87.9%.Four of the IHC(++) cases had haplotype of chromosome 17, with a positive rate of 5.26% (4/76) of the FISH positive cases.Five of the IHC(+++)cases had polyploid of chromosome 17, with a negative rate of 2.9% (5/172) of the FISH negative cases, indicating IHC results could better reflect FISH results.

Conclusions

Nuclei and tissue microarrays technique can be used in detecting HER-2 gene amplification and protein expression, and has the advantages of low cost and relatively reliable results.

Key words: tissue microarray, immunohistochemistry, fluorescence in situ hybridization, HER-2, breast carcinoma