METHODS: Using data from a multicenter study of 1,126 Asian patients with ovarian cancer (including 147 BRCA PV carriers), we developed models incorporating cancer history, clinicopathologic features, and reproductive factors to estimate the likelihood of carrying PVs. We assessed discrimination, calibration, and accuracy and compared genetic testing costs with a universal testing strategy.
RESULTS: Our final model demonstrated good calibration and strong discriminatory power, with an area under the curve of 0.80 (95% confidence interval, 0.74-0.87). Factors included in the model were age at diagnosis, ethnicity, personal and family cancer history, and clinicopathologic features. The model had 77% accuracy at the optimal threshold for testing compared with 13% accuracy with universal testing, reducing genetic testing costs from ∼USD4,371 to ∼USD1,974 per identified carrier. Notably, while maintaining 100% sensitivity, the model reduced testing by 15%, yielding potential savings of ∼USD68,182 per 800 patients each year.
CONCLUSIONS: Targeted testing using a prediction model potentially offers a more efficient and scalable alternative when universal testing is not feasible, optimizing impact in resource-limited settings.
IMPACT: This work supports more affordable and equitable BRCA testing pathways for Asian patients with ovarian cancer.
METHODS: The Mainstreaming Genetic Counselling for Ovarian Cancer Patients (MaGiC) study is a prospective, two-arm observational study comparing oncologist-led and genetics-led counselling. This study included 790 multiethnic patients with ovarian cancer from 23 sites in Malaysia. We compared the impact of different method of delivery of genetic counselling on the uptake of genetic testing and assessed the feasibility, knowledge and satisfaction of patients with ovarian cancer.
RESULTS: Oncologists were satisfied with the mainstreaming experience, with 95% indicating a desire to incorporate testing into their clinical practice. The uptake of genetic testing was similar in the mainstreaming and genetics arm (80% and 79%, respectively). Patient satisfaction was high, whereas decision conflict and psychological impact were low in both arms of the study. Notably, decisional conflict, although lower than threshold, was higher for the mainstreaming group compared with the genetics arm. Overall, 13.5% of patients had a pathogenic variant in BRCA1 or BRCA2, and there was no difference between psychosocial measures for carriers in both arms.
CONCLUSION: The MaGiC study demonstrates that mainstreaming cancer genetics is feasible in low-resource and middle-resource Asian setting and increased coverage for genetic testing.