HER-2 gene amplification by fluorescence in situ hybridization (FISH) compared with immunohistochemistry (IHC) in breast cancer: a study of 528 equivocal cases.
The concordance rate between fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) on evaluating HER-2/neu status is still controversial, especially for the IHC 2+/equivocal cases. In this study, we investigated the amplification of HER-2/neu gene by FISH in IHC (2+)/equivocal specimens to clarify the correlation between HER-2/neu and clinicopathologic features of breast cancers. HER-2/neu amplification was determined by FISH on 528 specimens of breast carcinomas with equivocal expression of HER-2/neu protein by IHC detection. 65.5 % of IHC 2+ patients were negative for HER-2/neu amplification, 29.0 % were positive and the remaining was equivocal. A statistically significant inverse association was found between hormone receptor expression and HER-2/neu amplification (P < 0.05). Furthermore, polysomy of CEP17 was detected in 60 % of breast carcinomas. The results highlight the necessity of FISH test for further categorization when breast carcinoma cases are scored 2+ by IHC.
Department of Pathology, the First Affiliated Hospital of Zhejiang University, Qingchun Road 79#, Hangzhou, Zhejiang, China. z8354335@yahoo.com.cn
Han
H
Zhang
Guoping
G
Ren
Xiaoling
X
Wang
Jing
J
Zhao
Hongtian
H
Yao
Yanfeng
Y
Bai
Wang
W
Bo
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism*; D002277:Carcinoma / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism*; D002886:Chromosomes, Human, Pair 17; D005260:Female; D005784:Gene Amplification; D018628:Gene Dosage; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics*
D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human