Background: Polygenic risk scores (PRS) are clinically available for risk stratification to guide prevention and screening management in oncology, despite guidelines that recommend against this. Most data used to generate PRS come from populations of European descent, raising concerns about the contribution of PRS to existing health disparities. In addition, awareness of higher breast cancer-specific mortality and the increased risk of triple-negative breast cancer in Black women may play an implicit or explicit role in genetic counselors’ (GCs’) clinical risk assessments.
Methods: To explore how cancer GCs interpret PRS in cancer risk management and the potential impact of patient race, we conducted a survey of risk assessment and management before and after incorporating PRS into two clinical vignettes. 170 cancer GCs were randomized to see one of two sets of vignettes of cancer genetic counseling involving PRS results, with the only difference being patient self-identified race (White vs Black).
Results: PRS that elevated or lowered risk relative to the standard of care model, Tyrer-Cuzick, were associated with corresponding increases and decreases in risk perception, respectively. Patient race did not impact pre- and post-PRS assessment or levels of support for prevention strategies except for prophylactic mastectomy. Few GCs recommended prophylactic mastectomy, but some GCs were slightly more likely to recommend prophylactic mastectomy to Black rather than White patients regardless of whether PRS predicted higher or lower lifetime risk than Tyrer-Cuzick model.
Conclusion: These results forecast ethical concerns about inequities in future PRS clinical implementation and in cancer genetic counseling more generally.
Authors: Yifei Sylvia Lin, NIH/Johns Hopkins Genetic Counseling Graduate Program; Susan Persky, National Human Genome Research Institute, National Institute of Health; Genevieve Wojcik, Johns Hopkins University; Kathy Helzlsouer, National Institutes of Health
