ERBB2 Mutation Testing in NSCLC: A Pan-European Real-World Evaluation of the Oncomine Precision Assay

Background/Objectives: The non-small-cell lung cancer (NSCLC) therapeutic landscape has undergone a profound transformation with the introduction of multiple personalized treatment options. Mutations in ERBB2 (HER2) have recently emerged as promising novel targets for the treatment of non-squamous NSCLC (nsNSCLC). Accurate, rapid, and efficient molecular profiling is crucial for identifying patients who may benefit from targeted therapies, including HER2-directed agents. Materials and Methods: Here, we aimed to retrospectively assess the performance of the Oncomine™ Precision Assay* (OPA) in combination with the Ion Torrent Genexus™ Integrated Sequencer* (Thermo Fisher Scientific. Waltham, MA, USA) for detecting ERBB2 mutations in nsNSCLC. A total of 108 archived nsNSCLC samples, consisting of biopsies, resections, and cytological specimens, were used to assess concordance with in-house-validated orthogonal tests. Results: The OPA showed high sensitivity and specificity with an overall accuracy of 100% for single-nucleotide variants (SNVs) and insertions and deletions (Indels). SNVs and Indels with allele frequencies as low as 5% were correctly identified across samples with a tumor cell content ranging from 5% to 95%. Additionally, the assay demonstrated high reproducibility across the six participating laboratories. The turnaround time of the OPA was notably shorter compared to traditional orthogonal methods, facilitating rapid molecular report generation. Conclusions: The OPA in combination with the Ion Torrent Genexus™ System allows for highly sensitive and specific detection of relevant ERBB2 mutations. The assay’s streamlined workflow, coupled with its automated data analysis pipeline, enables a fast turnaround time for testing across a range of sample types. This includes samples with reduced tumor cell content and limited available input. This study demonstrates the future potential of using this assay in a clinical setting.