Detecting intratumoral heterogeneity in routine breast-HER2 testing: low yield of testing multiple blocks

Intratumoral heterogeneity can lead to uncertainty in breast carcinoma HER2 testing, both with respect to pathology reporting and clinical significance. The standard practice is to perform breast biomarker testing on a single representative section of tumor; however, concern over heterogeneity often leads to testing on additional tissue blocks. Our objective was to assess the diagnostic yield of testing multiple blocks of a single invasive breast carcinoma.
Source: Annals of Diagnostic Pathology - Category: Pathology Authors: Source Type: research