Presented at the recent Association for Molecular Pathology (AMP) 2021 conference our two posters are now available for download. Details of the presentations are as follows:
Poster 1: US Adoption of Tumor Mutation Burden (TMB) Testing for Non-Small Cell Lung Cancer (NSCLC) patients in Clinical Routine Practice: Is now ready for primetime
Tumor Mutation Burden measures patient tumor mutation quantity. High TMB status clinically correlates with better Immune Checkpoint Inhibitor (ICI) therapy outcomes. Several methods and definitions exist to measure patient TMB status.
Today, guidelines classify TMB as an emerging biomarker, and acknowledge no consensus exists on how to test for TMB status. However, an approved therapy with a targeted Next Generation Sequencing (NGS) panel-based Companion Diagnostic (CDx) provides a TMB-High status definition linked to a single ICI.
In this poster we evaluate TMB testing availability, adoption, and methods used to assess US NSCLC patients utilizing our Diagnostic Network for Precision Medicine (DXRX) data platform to access Real-world data from 106,076 patients diagnosed with NSCLC from Q1 2019 to Q3 2020.
Key findings of the Study:
•NSCLC patients’ receiving TMB testing has grown to more than half of those tested for PD-L1.
•The rapid increase of TMB testing rate in parallel with reduced PD-L1 testing may, in part, be due to the FDA approval of a PD-L1 inhibitor and CDx assay using a TMB score ≥ 10 muts/Mb for patients with solid tumors.
•The number of labs offering TMB testing has increased by ~50%.
•Despite emerging biomarker status in guidelines, differences in panel size, and cut-offs, TMB testing adoption and availability for NSCLC patients is growing.
•There is potential for the TMB testing landscape to evolve like the PD-L1 landscape, with multiple CDx tests associated with different ICI therapies.
Taking the learnings from the PD-L1 testing landscape, it will be important to ensure comprehensive harmonization collaborations and studies are established to ensure standardization of testing and selection of the right patients for ICI treatment.
Authors: Anthony M Magliocco MD3 and Kenneth J. Bloom MD FCAP4 ,Peter V. Riccelli PhD2, Lynn Replogle MBA2, Karen Keating PhD1, Annie Tapley1, Lauren Parnham1, Lyam Buchanan BSc1, Derry Mae Keeling BSc1, Susanne Munksted MSc1, Jordan Clark MPhil1
Poster 2: Microsatellite Instability/Mismatch Repair (MSI/MMR): A Cancer Risk Marker Today, Rapidly Evolving into a Predictive Biomarker for Tomorrow
MSI and MMR are well established diagnostic risk biomarkers for Lynch Syndrome (LS). Predictive clinical utility of MSI/MMR status is evolving, with 2 therapy approvals identifying pan-tumor and endometrial cancer patients eligible for Immune Checkpoint Inhibitors (ICI).
Today, MSI/MMR testing for solid tumors is recommended to evaluate for LS and to predict therapy response. Sufficient adoption of MSI/MMR testing depends on physician awareness of clinical utility, test availability and adequate reimbursement. Either Microsatellite Instability-High (MSI-H) or a Deficient DNA Mismatch Repair (dMMR) result is required to prescribe therapy. This could lead to confusion and disparity between MSI and MMR testing.
We assessed the US solid tumor testing landscape utilizing our Diagnostic Network for Precision Medicine (DXRX) data platform. Real-world data from 52,037 patients between Q3 2017 to Q3 2020 was used to calculate MSI and MMR testing rates across the following metastatic tumor indications: Non-Small Cell Lung Cancer (NSCLC), bladder cancer, cervical cancer, Colorectal Cancer (CRC), Triple-Negative Breast Cancer (TNBC) and Gastrointestinal Stromal Tumor (GIST). One hundred and fifty-nine labs were also profiled to assess in-house MSI and MMR testing capabilities and methodology.
Key findings of the Study:
•Increased testing rates are likely driven by the pan-tumor PD-L1 inhibitor approval for MSI/MMR.
•Despite a shorter turnaround time and lower cost associated with IHC, MMR testing rates remained stable or decreased.
•The increase in MSI testing rates implies a shift towards the adoption of comprehensive NGS testing in oncology to identify multiple actionable biomarkers.
•Factors such as lack of clear, consistent MSI/MMR testing recommendations and awareness of clinical utility across cancer indications may be causing variations in testing rates. Improving these factors will drive continued adoption of MSI/MMR testing to predict therapy efficacy.
Authors: Kenneth J. Bloom MD FCAP4 ,Anthony M Magliocco MD3,Charlotte White BSc1, Peter V. Riccelli PhD2, Lauren Parnham1, Lyam Buchanan1, Priscilla Cirillo PhD1, Lily Handley1, Shilpa Haridas1 Susanne Munksted MSc1, Jordan Clark MPhil1
Interested in discussing further? Our authors would be delighted to receive your questions, contact us via [email protected]