HRD testing
Pronunciation: H-R-D
Also written as: HRD — Homologous Recombination Deficiency
Laboratory analysis to detect homologous recombination deficiency in tumors, used to guide PARP inhibitor therapy.
Full Definition
HRD testing (homologous recombination deficiency testing) is a genomic assay that evaluates a tumor's ability to repair DNA through homologous recombination pathways. Tumors with HRD are characterized by specific genomic signatures including loss of heterozygosity, telomeric allelic imbalance, and large-scale state transitions. HRD-positive tumors, regardless of BRCA mutation status, show enhanced sensitivity to platinum chemotherapy and PARP inhibitors. This testing has become increasingly important for treatment selection in ovarian cancer, helping identify patients most likely to benefit from targeted therapies.
Usage
Usage note: HRD is always capitalized; distinguish from other genomic tests like MSI or BRCA testing.
In Context
- "HRD testing revealed a positive score of 60, indicating deficient homologous recombination repair." — Molecular pathology report
- "The tumor was HRD-positive by genomic instability score, supporting PARP inhibitor maintenance therapy." — Oncology consultation note