(262) The diagnostic landscape of HRD testing based on cross-sectional survey of physicians and molecular biologists conducting testing (INDICATOR ONE)

Publication Number: 922

Background: Homologous recombination deficiency (HRD) occurs in ~50% of epithelial ovarian cancer (OC) cases. As HRD+ tumors are more sensitive to poly(ADP-ribose) polymerase inhibitors (PARPi), HRD testing (determined by BRCAm and genomic instability score) identifies advanced OC (AOC) patients who will benefit most from a PARPi. Guidelines recognize the value of these tests to inform PARPi maintenance treatment decisions following first-line chemotherapy.

Objectives: To characterize the HRD testing landscape in the US and Europe (UK, France, Germany, Austria).

Methods: This first of 3 waves of a non-interventional, cross-sectional, survey was open Jul-Nov 2022. Participants were recruited from clinical sites/laboratories known to conduct HRD testing and via a standing physician panel.

Results: Responses were received from 287 eligible participants (representing invitees from ~9% sites and < 2% panelists), 265 of whom completed the full survey (Europe: 153, US: 112; 228 physicians, 37 clinical laboratory heads/molecular biologists). Physicians ordered HRD testing for 70% ± 27% (mean ± SD) of newly diagnosed AOC patients. Nearly all physicians ordered the test to inform treatment decisions (n=222; 97%). Physicians were most likely to conduct testing at stage 3 or 4 of OC diagnosis (Europe: n=89, 64%; US: n=63, 71%), followed by OC diagnosis regardless of stage (Europe: n=51, 37%, US: n=51, 57%). When European participants selected all types of tests used, MyChoice® CDx, Myriad Genetics (n=82, 54%) was most common, followed by FoundationOne® CDx, Foundation Medicine (n=38, 25%). US participants mostly used FoundationOne CDx (n=62, 55%), followed by MyChoice CDx (n=49, 44%), and QIAGEN QIASeq HRD (n=38, 34%). Test costs were often partially (Europe: n=47; 27%; US: n=125; 53%) or fully covered (Europe: n=89; 51%; US: n=48; 21%). Results were received within 10 ± 6 (mean ± SD) working days in the US and 16 ± 11 working days in Europe. Testing guided treatment decisions ‘always/often’ (Europe: n=117, 84%; US: n=65, 73%) or ‘sometimes’ (Europe: n=21, 15%; US: n=23, 26%). Most European (n=108, 78%) and US (n=71, 80%) institutions offered genetic counselling.

Conclusions: Among physicians and molecular biologists known to be conducting HRD testing, most newly diagnosed AOC patients were tested for HRD, and results usually played a role in treatment decisions. Variations in testing between the US and Europe include test types, test cost coverage, and time to receive results. Differences indicate potential areas for improvement in HRD testing to further benefit patients.
© 2023 American Society of Clinical Oncology, Inc. Reused with permission. This abstract was accepted and previously presented at the 2023 ASCO Annual Meeting. All rights reserved.