AMP Releases Consensus Guidelines for Homologous Recombination Deficiency (HRD) Testing in Cancer
The Association for Molecular Pathology (AMP), the leading global organization for molecular diagnostics, has published new best practice recommendations for clinical laboratories conducting homologous recombination deficiency (HRD) testing. The guidelines are detailed in a manuscript titled “Recommendations for Clinical Molecular Laboratories for Detection of Homologous Recombination Deficiency in Cancer,” a collaborative effort with the Association of Community Cancer Centers and the College of American Pathologists. The full text is now freely accessible online in The Journal of Molecular Diagnostics.
HRD testing plays a critical role in identifying tumors with impaired DNA repair via the homologous recombination pathway. Such tumors often exhibit genomic instability and may be more responsive to targeted therapies, particularly PARP (poly ADP-ribose polymerase) inhibitors. However, current HRD assays vary significantly in their definitions, biomarker targets, and algorithms—differences that can influence treatment choices.
To address this, AMP convened an expert panel under its Clinical Practice Committee to review the scientific literature and current laboratory practices. The resulting consensus recommendations aim to support standardization and quality assurance in HRD testing. The working group included representation from major oncology and pathology societies, including ASCO and CAP.
Dr. Alanna J. Church, Chair of AMP’s 2025 Clinical Practice Committee and Associate Director of Molecular Pediatric Pathology at Dana-Farber/Boston Children’s Cancer Center, emphasized the need for harmonization. “Our review revealed wide variability in assay design, tumor sample types, and biomarker selection,” she noted. “These evidence-based guidelines aim to improve consistency, transparency, and ultimately, patient care.”
The working group formulated 12 key recommendations focusing on assay design, validation, and the clinical interpretation of HRD-related genomic features. These guidelines are informed by professional expertise, survey data, and analysis of over 4,300 scientific publications. They provide direction on interpreting genomic scars from both tumor and germline sequencing data and outline the clinical implications of various HRD biomarkers.
Dr. Susan Hsiao, Chair of the HRD Working Group and Associate Professor of Pathology at Columbia University, added, “Our goal is to help clinical labs navigate the complexities of HRD testing while identifying areas where further research is needed. As technologies and our understanding of HRD evolve, AMP remains dedicated to updating and refining these recommendations.”