Determination of HER2 amplification in primary breast cancer using dual-colour chromogenic in situ hybridization is comparable to fluorescence in situ hybridization: a European multicentre study involving 168 specimens

• Published in: Histopathology Vol. 56; no. 4; pp. 472 - 480
• Main Authors: García-Caballero, Tomás, Grabau, Dorthe, Green, Andrew R, Gregory, John, Schad, Arno, Kohlwes, Elke, Ellis, Ian O, Watts, Sarah, Mollerup, Jens
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.03.2010; Blackwell
• Subjects: Basic Medicine; Biological and medical sciences; breast cancer; Breast Neoplasms - diagnosis; Breast Neoplasms - genetics; Breast Neoplasms - metabolism; Cell and Molecular Biology; Cell- och molekylärbiologi; CEN-17; Centromere - chemistry; Centromere - metabolism; CISH; Color; Europe; Female; FISH; Gene Amplification - genetics; Genes, erbB-2; Gynecology. Andrology. Obstetrics; HER2; HER2 amplification; Humans; hybridization; Hybridization, Genetic; in situ; in situ hybridization; In Situ Hybridization - methods; In Situ Hybridization, Fluorescence; Investigative techniques, diagnostic techniques (general aspects); Mammary gland diseases; Medical and Health Sciences; Medical sciences; Medicin och hälsovetenskap; Medicinska och farmaceutiska grundvetenskaper; Microscopy; Microscopy, Fluorescence; Neoplasms - genetics; Original; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Tumors; Europe; Molecular hybridization; CEN-17; Breast disease; CISH; Color; erbB2 Gene; Breast cancer; Malignant tumor; Chromogenic In Situ Hybridization; Human Epidermal growth factor Receptor 2; Amplification; Mammary gland diseases; Anatomic pathology; C-Onc gene; Fluorescence in situ hybridization; HER2 amplification; FISH; HER2; Protooncogene; Cancer; Primary cancer; in situ hybridization
• ISSN: 0309-0167; 1365-2559
• DOI: 10.1111/j.1365-2559.2010.03503.x

García‐Caballero T, Grabau D, Green A R, Gregory J, Schad A, Kohlwes E, Ellis I O, Watts S & Mollerup J
(2010) Histopathology56, 472–480
Determination of HER2 amplification in primary breast cancer using dual‐colour chromogenic in situ hybridization is comparable to fluorescence in situ hybridization: a European multicentre study involving 168 specimens Aims:  Fluorescence in situ hybridization (FISH) can be used to reveal several genomic imbalances relevant to proper cancer diagnosis and to the correct treatment regime. However, FISH requires expensive and advanced fluorescence microscopes in addition to expertise in fluorescence microscopy. To determine whether a newly developed dual‐colour chromogenic in situ hybridization (CISH) method is a suitable alternative to FISH, we analysed the human epidermal growth factor receptor 2 gene (HER2) amplification level of 168 breast cancer specimens using dual‐colour CISH and FISH and compared the results. Methods and results:  We found 100% agreement between HER2 status determined by FISH and dual‐colour CISH. Furthermore, we observed that the time used to score slides was significantly reduced by 28% in dual‐colour CISH compared with the FISH protocol. Concordance between HER2 protein status and dual‐colour CISH or FISH was equally good with an overall agreement of 96.8%. Correlation between the HER2/centromere 17 gene ratios obtained with dual‐colour CISH and FISH was highly significant with an overall correlation coefficient (ρ) of 0.96. Conclusions:  We conclude that dual‐colour CISH and bright field microscopy are excellent alternatives to FISH when analysing the HER2 status of primary breast cancer.