Age at diagnosis may trump family history in driving BRCA testing in a population of breast cancer patients.

BACKGROUND

Standard BRCA genetic testing criteria include young age of diagnosis, family history, and Jewish ancestry. The purpose of this study was to assess the effect of these criteria on BRCA test utilization in breast cancer patients.

METHODS

Breast cancer patients aged 18 to 64 years living in Pennsylvania in 2007 completed a survey on family history of breast and ovarian cancer and BRCA testing (N = 2,213). Multivariate logistic regression was used to estimate odds of BRCA testing by patient characteristics, and predicted probabilities of testing were calculated for several clinical scenarios.

RESULTS

Young age at diagnosis (<50 years) was strongly associated with BRCA testing, with women diagnosed before age 50 years having nearly five times the odds of receiving BRCA testing compared to women diagnosed at age 50 or older (OR = 4.81; 95% CI, 3.85-6.00; P < 0.001). Despite a similar BRCA mutation prevalence estimate (8-10%), a young Jewish patient <50 years with no family history had markedly higher predicted probability of testing (63%) compared with an older, non-Jewish breast cancer patient with more than one first-degree relative (43%).

CONCLUSION

Age at diagnosis, Jewish ancestry, and both maternal and paternal family history are strongly predictive of BRCA testing. However, among women diagnosed at age 50 or older, family history may be an underused criterion that may benefit from targeted intervention.

IMPACT: Robust methods specific to ascertaining detailed family history, such as through electronic medical records, are needed to accurately identify patients for BRCA testing.