Performance Assessment of a Locally Semi-Automated NGS-Based Workflow for Homologous Recombination Deficiency Testing in High-Grade Serous Ovarian Carcinoma

Background/Objectives: Homologous recombination deficiency (HRD) is a predictive biomarker in high-grade serous ovarian carcinoma for platinum-based chemotherapy and PARP inhibitors. The implementation of HRD testing in routine diagnostics has generated multiple commercial assays that differ in genomic targets, bioinformatic analysis, and HRD scoring strategies. We aimed to assess the analytical performance and feasibility of a locally semi-automated workflow based on the Agilent SureSelect CD HRR17 panel with SeqOne/SomaHRD analysis, and to compare it with established commercial HRD assays currently used in routine clinical practice: Myriad MyChoice CDx and SOPHiA DDM Dx HRD Solution. Methods: Thirty high-grade serous ovarian carcinoma cases diagnosed between 2019 and 2023 were retrospectively analyzed. HRD status was assessed with the Agilent-SeqOne workflow and compared with Myriad (n = 12) and SOPHiA (n = 18). Concordance and correlation between genomic instability metrics were evaluated. Results: The Agilent/SeqOne workflow showed high concordance with both comparison workflows. Genomic instability metrics strongly correlated across assays (R2 up to 0.96). A lower proportion of inconclusive classifications was observed with the Agilent/SeqOne workflow. Discordances were mainly observed in borderline cases near classification thresholds. Variant detection was highly concordant within shared genomic regions. Conclusions: The locally semi-automated HRD workflow demonstrated high analytical concordance with established commercial assays in evaluable cases. Operational advantages related to workflow flexibility and local reanalysis support its potential implementation in routine molecular diagnostics.