Open AccessER and PR Immunohistochemistry and HER 2 FISH versus Oncotype DX : Implications for Breast Cancer Treatment
Author(s) -
Park MiHee M.,
Ebel Joshua J.,
Zhao Weiquiang,
Zynger Debra L.
Publication year - 2013
Publication title -
the breast journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.533
H-Index - 72
eISSN - 1524-4741
pISSN - 1075-122X
DOI - 10.1111/tbj.12223
Subject(s) - medicine , concordance , breast cancer , immunohistochemistry , oncology , fish <actinopterygii> , trastuzumab , estrogen receptor , biomarker , fluorescence in situ hybridization , cancer , gynecology , gene , biology , biochemistry , fishery , chromosome
Estrogen receptor ( ER ), progesterone receptor ( PR ), and human epidermal growth factor ( HER 2) concordance between immunohistochemistry ( IHC ) and fluorescence in situ hybridization ( FISH ), and Oncotype DX , a commercially available RT ‐ PCR ‐based assay which recently began reporting biomarker results was assessed. ER concordance was 98.9% (262/265), Pearson correlation coefficient ( r ) = 0.42, and Spearman's rank correlation (ρ) = 0.25. Positive percent agreement for ER was 98.9% (262/265). One patient with discordant ER results was not offered hormone therapy based on the preferential use of Oncotype DX . PR was concordant in 91.3% (242/265), r = 0.80, ρ = 0.75, and Cohen's kappa (κ) = 0.63. Positive percent agreement for PR was 90.5% (218/241) and negative percent agreement was 100% (24/24). HER 2 concordance was 99.2% (245/247), r = 0.35, ρ = 0.28, and κ = 0.12. Positive percent agreement for HER 2 was 0% (0/2) and negative percent agreement was 100% (245/245). Of the three FISH HER 2‐amplified cases, two were negative and one was equivocal, and all FISH HER 2‐equivocal cases ( n = 3) were negative by Oncotype DX . Patients that were FISH HER 2‐amplified, Oncotype DX HER 2‐negative did not receive trastuzumab. Although our results demonstrated high concordance between IHC and Oncotype DX for ER and PR , our data showed poor positive percent agreement for HER 2. Compared to FISH , Oncotype DX does not identify HER 2‐positive breast carcinomas. The preferential use of Oncotype DX biomarker results over IHC and FISH is discouraged.