Indian Journal of Pathology and Microbiology
Home About us Instructions Submission Subscribe Advertise Contact e-Alerts Ahead Of Print Login 
Users Online: 1257
Print this page  Email this page Bookmark this page Small font sizeDefault font sizeIncrease font size
Year : 2020  |  Volume : 63  |  Issue : 2  |  Page : 194-199

Dual-color dual-hapten in situ hybridization (D-DISH) – Comparison with fluorescence in situ hybridization (FISH) for HER2/neu testing in breast cancer

Department of Pathology, Tata Memorial Hospital, Mumbai, Maharashtra, India

Correspondence Address:
Tanuja M Shet
Department of Histopathology, 8th Floor, Annexe Building, Tata Memorial Centre, Dr E Borges Road, Parel, Mumbai - 400 012, Maharashtra
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/IJPM.IJPM_861_19

Rights and Permissions

Context: HER2/neu testing in breast cancer is a mandate due to availability of trastuzumab, a monoclonal antibody targeted against this biomarker. Dual-color dual-hapten in situ hybridization (D-DISH) is a new test for assessment of HER2/neu gene overexpression on light microscopy. Aims: This was a validation study for D-DISH in our laboratory and was conducted to study the concordance between fluorescence in situ hybridization (FISH) and D-DISH for HER2/neu testing in breast cancer. Materials and Methods: In all, 150 cases of invasive breast carcinoma requested for FISH analysis were selected. Immunohistochemistry by Ventana PATHWAY anti-HER2/neu (4B5) antibody, FISH by ZytoLight SPEC ERBB2/CEN17 Dual Color Probe, and D-DISH using the Ventana INFORM HER2 Dual ISH DNA Probe Cocktail Assay was carried out. Statistical Analysis: Cohen's kappa coefficient was used to calculate concordance between FISH and D-DISH assays. The ratios and average number of signals were compared with Lin's concordance correlation coefficient. Results: About 93.1% of the cases showed concordance between FISH and D-DISH results. Cohen's kappa correlation coefficient was 0.836, indicating almost perfect level of agreement. Lin's concordance correlation coefficient (ρc) showed moderate strength of agreement for HER2/chromosome 17 ratios between FISH and D-DISH assays (ρc 0.9452). As per the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) 2018 updated guidelines, four of the cases that were nonamplified on FISH showed low-level amplification on D-DISH due to counting errors caused by faint signals or background dust. Genomic heterogeneity and larger red chromosome 17 signals on D-DISH led to discordance of the six cases amplified by FISH. D-DISH failure rate was 3.33%. Conclusion: Overall, D-DISH showed good concordance with FISH but needs expertise for reporting.

Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)

 Article Access Statistics
    PDF Downloaded139    
    Comments [Add]    

Recommend this journal