Patient uptake of updated genetic testing following uninformative BRCA1 and BRCA2 results

Abstract

Advances have dated the genetic testing initially offered to evaluate for hereditary breast and ovarian cancer risks. Previous research has demonstrated that many patients have not updated testing. This study reviewed the incidence of additional analysis after an uninformative BRCA1/2 result and offered updated testing with limited barriers to those who had not completed. After viewing an educational video and providing informed consent, eligible patients were mailed a saliva collection kit to complete an 84-gene hereditary cancer panel at no personal cost. A total of 704 patients had completed BRCA1/2 only testing between 2001 and 2020. Fifteen percent (N = 102) of the 671 patients with an uninformative BRCA1/2 result had already completed expanded testing. Most, 74 of 102 (73%), had been rereferred to medical genetics during a clinical visit related to cancer care. Those who had already completed additional testing were more likely to have a personal history of cancer (92% vs. 79%, p = 0.002) and live locally (p = 0.032). Invitation to complete updated testing through this study was sent to 372 people, and 116 (31%) consented to participate. For 142 of the 256 who did not proceed with testing through the study, proof of receipt of research information was available. In total, 22 pathogenic variants were reported in 21 of the 226 patients with updated testing from before and including our study: ATM (4), CHEK2 (4), LZTR1 (1), MUTYH (3), NBN (1), NF1 (1), NTHL1 (1), PALB2 (4), PMS2 (1), RAD50 (1), and SPINK1 (1). Many potential barriers of retesting were eliminated by removing personal costs or travel requirements. Still, only about 30% of patients agreed to participate, and a significant portion elected not to proceed. Future research could focus on the discovery of other factors that dissuade patients and what measures may better inform them on potential benefits.

Keywords: BRCA1/2; genetic counseling; genetic testing; health behavior; hereditary cancer; referral practices; uninformative results.