Evaluation of HER-2/neu gene amplification and overexpression: Comparison of frequently used assay methods in a molecularly characterized cohort of breast cancer specimens

• Published in: Journal of clinical oncology Vol. 20; no. 14; pp. 3095 - 3105
• Main Authors: PRESS, Michael F, SLAMON, Dennis J, FLOM, Kerry J, PARK, Jinha, ZHOU, Jian-Yuan, BERNSTEIN, Leslie
• Format: Journal Article
• Language: English
• Published: Baltimore, MD Lippincott Williams & Wilkins 15-07-2002
• Subjects: Antibodies, Monoclonal; Biological and medical sciences; Biomarkers, Tumor - genetics; Breast Neoplasms - chemistry; Breast Neoplasms - genetics; Cohort Studies; Evaluation Studies as Topic; Female; Gene Amplification; Gene Expression Regulation, Neoplastic; Genes, erbB-2 - genetics; Genital system. Mammary gland; Humans; Immunoenzyme Techniques; Immunohistochemistry; In Situ Hybridization, Fluorescence; Investigative techniques, diagnostic techniques (general aspects); Medical sciences; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Up-Regulation; Human; Immunohistochemistry; Carcinoma; Gene overexpression; Malignant tumor; Pathology; Mammary gland diseases; Gene amplification; Investigation method; C-Onc gene; Fluorescence in situ hybridization; Genetics; Mammary gland; Molecular biology; Comparative study; Protooncogene
• ISSN: 0732-183X; 1527-7755
• DOI: 10.1200/jco.2002.09.094

To compare and evaluate HER-2/neu clinical assay methods.
One hundred seventeen breast cancer specimens with known HER-2/neu amplification and overexpression status were assayed with four different immunohistochemical assays and two different fluorescence in situ hybridization (FISH) assays.
The accuracy of the FISH assays for HER-2/neu gene amplification was high, 97.4% for the Vysis PathVision assay (Vysis, Inc, Downers Grove, IL) and 95.7% for the the Ventana INFORM assay (Ventana, Medical Systems, Inc, Tucson, AZ). The immunohistochemical assay with the highest accuracy for HER-2/neu overexpression was obtained with R60 polyclonal antibody (96.6%), followed by immunohistochemical assays performed with 10H8 monoclonal antibody (95.7%), the Ventana CB11 monoclonal antibody (89.7%), and the DAKO HercepTest (88.9%; Dako, Corp, Carpinteria, CA). Only the sensitivities, and therefore, overall accuracy, of the DAKO Herceptest and Ventana CB11 immunohistochemical assays were significantly different from the more sensitive FISH assay.
Based on these findings, the FISH assays were highly accurate, with immunohistochemical assays performed with R60 and 10H8 nearly as accurate. The DAKO HercepTest and the Ventana CB11 immunohistochemical assay were statistically significantly different from the Vysis FISH assay in evaluating these previously molecularly characterized breast cancer specimens.