Premium
Comparison of HER2 immunohistochemical results using a monoclonal antibody (SV2‐61γ) and a polyclonal antibody (for Dako HercepTest) in advanced gastric cancer
Author(s) -
Tamura Gen,
Osakabe Mitsumasa,
Yanagawa Naoki,
Ogata Shinya,
Nomura Takashi,
Fukushima Norimasa,
Ito Yoshimasa,
Tabuchi Minori
Publication year - 2012
Publication title -
pathology international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.73
H-Index - 74
eISSN - 1440-1827
pISSN - 1320-5463
DOI - 10.1111/j.1440-1827.2012.02843.x
Subject(s) - immunohistochemistry , polyclonal antibodies , monoclonal antibody , monoclonal , antibody , pathology , medicine , cancer , microbiology and biotechnology , biology , immunology
We compared a monoclonal antibody (SV2‐61γ) and a polyclonal antibody (Dako HercepTest) in immunohistochemical assessments of human epidermal growth factor receptor 2 (HER2) expression in 73 samples of advanced gastric cancer. Results were scored as 0 to 3+, and equivocal or discordant (SV2‐61γ/Dako HercepTest = 0/2+, 0/3+, 1+/3+ or 2+/3+) cases were subjected to fluorescence in situ hybridization (FISH) analysis. The frequencies of HER2 scores of 2+ or 3+ were 15.1% (11/73) using SV2‐61γ and 38.4% (28/73) using Dako HercepTest. All of the equivocal or discordant cases with a HER2 score of 3+ using Dako HercepTest exhibited amplification of the HER2 gene regardless of the HER2 score determined with SV2‐61γ. The results of the HER2 tests differed according to the antibodies used for immunohistochemistry that preceded FISH analysis, being 15.1% (11/73) using SV2‐61γ and 23.3% (17/73) using Dako HercepTest. Thus, therapeutic decisions might be markedly influenced by the selection of antibody used in the HER2 test.