Uptake And Patient-Related Outcomes Of Mainstreaming Genetic Testing - A Systematic Review And Meta-Analysis

Abstract

Introduction/Background Mainstreaming refers to genetic testing following cancer diagnosis provided by non-genetics members of the treating team. We assessed uptake and patient-reported outcomes of mainstreaming genetic testing. Methodology We followed a prospective protocol according to PRISMA guidelines (PROSPERO: CRD42023467312). We searched PubMed and the Cochrane Library from inception to June 2024. Our Population included adult patients offered mainstreaming genetic testing (Intervention). Outcomes included testing uptake, satisfaction, decisional conflict/regret, anxiety, depression, and cancer-related distress. Qualitative synthesis and random-effects meta-analyses were performed. Quality assessment was performed using the Methodological Index for Non-Randomised Studies (MINORS). Results Searches yielded 5314 studies; 29 studies (n=13219) were included, out of which 14 were on ovarian cancer(OC) (n=6039), 6 on breast cancer(BC) (n=4354), 3 on prostate cancer(PC) (n=772), 1 on endometrial cancer(EC) (n=302) and 5 on multiple cancers (n=1752). There were no studies for colorectal cancer(CRC). Pooled genetic testing uptake was 91%(95%CI=86-96, I2=99.6%, n=3885) across all cancers. Unselected testing uptake was 95%(95%CI=92-98%, I2=98.4%, n=3946), while family history/clinical criteria-based testing uptake was 80%(95%CI=63-97%, I2=99.0%, n=1996). Uptake for OC cases was 93%(95%CI=88-98%, I2=98.6%, n=2801), for BC 95%(95%CI=90-99%, I2=94.78%, n=981), for EC 99%(95%CI=98-100%, I2=0.0%, n=304) and for PC 73%(95%CI=47-99%, I2=98.8%, n=772). Pooled pre-test (24.24 (95%CI:23.34-24.14, I2=93.0%)) and post-test 16.11 (95%CI:15.27-16.96, I2=80.3%)) Decisional Conflict Scale scores were low (3 studies, n=681), decreasing from pre-test to post-test (p=0.03). On qualitative synthesis, pre- and post-test satisfaction scores were high (14 studies, n=3093). Decisional regret (4 studies, n=393), pre- and post-test depression scales (2 studies, n=252), and post-test distress (5 studies, n=773) were low. There was variability in reported pre-test (low-to-high, 4 studies, n=1079) and post-test anxiety (low-to-moderate, 5 studies, n=1231), and pre-test distress (low-to-moderate, 2 studies, n=594). Conclusion Mainstreaming genetic testing uptake is associated with high uptake and satisfaction, and low decision conflict, regret, and post-test distress. Quality and quantity of evidence across different types of cancers varies significantly.