Utilization of a Multi-modal Comprehensive Genomic and Immune Profiling Testing Strategy Results in a High Rate of Test Success and Detection of Clinically Relevant Biomarkers While Optimizing Tissue Usage.

Abstract

Background: Molecular profiling is quickly becoming standard for patients with advanced cancer, with an increasing number of biomarker-directed therapies and innovative precision diagnostics available. However, with the expansion of relevant biomarkers, clinicians often face challenges obtaining optimal detection from limited tumor tissue. Here, we present biomarker detection rates from comprehensive genomic and immune profiling (CGIP) performed as a component of routine clinical care using a multi-modal testing strategy.

Methods: CGIP was performed on 20,645 solid tumor specimens in a CAP/CLIA and NYS CLEP-certified reference laboratory, including DNA- and RNA-based next-generation sequencing (NGS), RNA gene expression profiling, and PD-L1 immunohistochemistry (IHC). RNA and DNA were co-extracted to optimize tissue usage. Clinical significance of detected biomarkers was classified in accordance with the joint consensus recommendations of the Association for Molecular Pathology (AMP), American Society of Clinical Oncology (ASCO), and the College of American Pathologists (CAP).

Results: Adequacy of specimens for analysis with each test component varied from 99.8% (20,612) for PD-L1 IHC to 87.7% (18,113) for RNA-based NGS. DNA-based NGS had a > 96.0% success rate across all result components (short variants, copy number alterations, and genomic signatures), while RNA-based NGS and gene expression profiling were successful for 92.1% (16,689) and 90.2% (17,275) of cases, respectively. Median turnaround time from specimen receipt in the testing laboratory to report delivery was 8 days (range 1-35). Within our cohort of 15,815 cases with complete results available, 61.0% (9650) had at least one tier 1 biomarker with known clinical significance, 88.8% (14,039) had at least one tier 2 biomarker with potential clinical significance, 57.5% (9,090) had both tier 1 and 2 biomarkers, and 7.7% (1216) had no clinically significant biomarkers detected. Biomarker detection rates varied across tumor types, increasing with the addition of testing modalities.

Conclusions: Utilization of a multi-modal CGIP testing strategy resulted in a high rate of test success and detection of clinically relevant biomarkers while optimizing tissue usage.