Assessment of dual-probe Her-2 fluorescent in situ hybridization in breast cancer by the 2013 ASCO/CAP guidelines produces more equivocal results than that by the 2007 ASCO/CAP guidelines.
Dual-probe fluorescence in situ hybridization (D-FISH) is a widely accepted method to determine the gene amplification status of human epidermal growth factor receptor 2 (Her-2). In 2013, the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) updated the guidelines on the Her-2 testing for invasive breast cancer (BCa). The interpretation criteria for D-FISH changed accordingly. In this study, we compared the Her-2 FISH statuses based on the 2013 and 2007 ASCO/CAP guidelines in 1931 cases of BCa with Her-2 D-FISH testing at our hospital. We analyzed the clinicopathologic features of cases with equivocal results by the 2013 ASCO/CAP guidelines. Although the guideline update significantly improved the detection rate of Her-2 amplification, it also significantly increased the rate of equivocal results, posing a dilemma for clinical management. The equivocal results had a good reproducibility. The distribution of D-FISH-equivocal cases did not correlate with Her-2 status by immunohistochemistry, suggesting that Her-2 D-FISH equivocality may not reflect Her-2 overexpression. Compared with Her-2-negative cases by D-FISH, Her-2 D-FISH-equivocal cases had higher Ki67 expression, higher histological grade, more frequent lymph node metastasis, and lower estrogen receptor α expression, indicating a group of BCa with worse prognosis. The clinical significance of Her-2-equivocal results by D-FISH warrants further investigation.
['Qian|Xiao-Long|XL|', 'Wen|Hannah Y|HY|', 'Yang|Yi-Ling|YL|', 'Gu|Feng|F|', 'Guo|Xiao-Jing|XJ|', 'Liu|Fang-Fang|FF|', 'Zhang|Lanjing|L|', 'Zhang|Xin-Min|XM|', 'Fu|Li|L|']
D001943:Breast Neoplasms D002503:Centromere D002886:Chromosomes, Human, Pair 17 D005260:Female D005784:Gene Amplification D006801:Humans D017404:In Situ Hybridization, Fluorescence D017410:Practice Guidelines as Topic D018719:Receptor, ErbB-2 D012680:Sensitivity and Specificity
Her-2 Breast cancer The 2013 ASCO/CAP guidelines Equivocal Dual-probe fluorescence in situ hybridization (D-FISH)