Gene Protein Assay(GPA): Unveiling Tumor Heterogeneity in HER2/neu Positive Breast Cancer
Authors: Dr. Tanuja Shet, Dr. Aditi Rathi
Introduction: HER2/neu gene amplification on Fluorescence in-situ hybridization (FISH) is defined as average HER2neu gene signals > 4 and HER2:CEP17 ratio of > 2, in breast cancer. However, with tumor heterogeneity interpretation of these cut-offs is challenging and some cases test as borderline. We attempted a study analyzing Gene protein assay (GPA) which combines HER2/neu immunohistochemistry (IHC), and D-DISH (dual color dual in-situ hybridization) assay to help resolve this issue.
Methods: A total of 31 cases reported as HER2/neu amplified with intermixed tumor heterogeneity on FISH were taken for this study. The original HER2/neu count was between 4 to 6 and ratio near 2 in most cases. GPA was done using 4B5 HER2/neu IHC and Roche/Ventana D-DISH kit on Ventana Ultra machine by doing IHC first followed by D-DISH.
Result: On GPA, 3/31 cases were reported as non-amplified, and the rest were amplified. Advantage of GPA was that it helped count D-DISH as per membrane staining and identified more tumor heterogeneity in contrast to FISH in six cases. The results of the remaining cases were the same.
Histology Abroad: Qatar
Histology Abroad: Italy
Histology Abroad: Liberia
Histology Abroad: Canada
Histology Abroad: Rwanda and Nigeria
Histology Abroad: United Kingdom
2020 Poster Podcast Interviews: P10- High-resolution histological preparation of Araneomorphae and Mygalomorphae chelicerae using a modified petrographic technique
2020 Poster Podcast Interviews: P09- A Modified Procedure For The Preparation of Rodent Heart Sections Using HistoGel Infusion
2020 Poster Podcast Interviews: P08- Utilizing Image Analysis to Evaluate Overuse of Hematoxylin and Eosin Staining Reagents from Multiple Manufacturers
2020 Poster Podcast Interviews: P03- Anatomy and mechanical properties of the fallopian tubes
Advice from a Histology Recruiter: Advocacy
Advice from a Histology Recruiter: Education Employers Look For
Advice from a Histology Recruiter: Career Planning
Histology Thanksgiving 2020
Histotech of the Decade: Interview with Freida Carson
AwardsCast: Arthropod Immunohistochemistry
AwardsCast: Travel Scholarships in the Age of COVID-19
AwardsCast: Mentoring the Next Generation
AwardsCast: Confidence is Key
HistoHelp: a Little "Chit"-Chatter
Create your
podcast in
minutes
It is Free
DNA Today: A Genetics Podcast
Museum of the Missing
Strange by Nature Podcast
Sasquatch Chronicles
Hidden Brain