Guidelines for HER2 reporting in breast cancer: Recommendations by the Malaysian Breast Pathology Working Group

This consensus aims to develop a standardised guideline for human epidermal growth factor-2 (HER2) immunohistochemistry interpretation and reporting in Malaysia to support optimal therapeutic decision-making and research compatibility. An expert committee comprising pathologists and oncologists from public, private, and academic institutions convened to review existing international recommendations and taking into the consideration of local healthcare resource variations. The committee aims to harmonise reporting terminology in the reporting of HER2 testing, with emphasis on HER2-low and HER2-ultralow categories. A standardised HER2 reporting is crucial to ensure Malaysian patients benefit equitably from emerging HER2-targeted therapies. We hope this guideline could prepare the national pathology community in leading the evolving landscape of breast cancer management.