| Popis: |
BackgroundThe accurate assessment of hormone receptors (ER and PR), HER2 and Ki-67 proliferative index provides meaningful information about breast cancer prognosis and prediction of therapy response. Immunohistochemistry, the most common method for evaluating these prognostic biomarkers, can be impacted by numerous variabilities due to pre-analytical/analytical factors and subjective interpretation by pathologists. The Xpert® Breast Cancer STRAT4, a RT-qPCR based system, can be used to classify breast invasive carcinomas based on the assessment of these 4 biomarkers. In this study, we investigated the accuracy of RT-qPCR based mRNA expression levels in a closed, single-use cartridge, automated system compared with the current gold standard, immunohistochemistry (IHC), and fluorescent in situ hybridization (FISH) for HER2 equivocal cases.Methods We evaluated ESR1, PGR, ERBB2 and MKi67 mRNA expression by Xpert Breast Cancer STRAT4 and ER, PR, HER2 and Ki67 by IHC (FISH for HER2 IHC 2+) in 200 formalin-fixed paraffin-embedded (FFPE) tissue blocks with invasive breast cancer, collected from the Pathology Department of Casablanca Ibn Rochd University Hospital.Results Concordance between Xpert ® Breast Cancer STRAT4 and IHC was 93.5% for ER, 83.51% for PR, 95% for HER2 (92% for IHC+FISH), and 81.20% for Ki67 (excluding intermediate IHC Staining 10 ≤ %IHC Conclusions We demonstrated globally a high concordance between centrally assessed IHC, IHC+FISH and mRNA measurements of ER/ESR1 and HER2/ERBB2, and a moderate agreement between PR/PGR and Ki67/MKi67. These findings provide an additional, objective, and quantitative assessment of tumor receptor status in breast cancer. |
