Utilization of breast cancer screening in a clinically based sample of women after BRCA1/2 testing

Abstract

We conducted a prospective, observational study to determine breast cancer screening practices among self-referred high-risk women who pursued genetic testing for BRCA1 and BRCA2 mutations. Of the 107 unaffected women included in this study, 41 were BRCA1/2 carriers and 66 women tested negative for a mutation previously identified in their family. All of the women underwent comprehensive pre- and posttest genetic counseling, and completed baseline and 12-month follow-up telephone interviews. The baseline (pretest) interview assessed potential predictors of mammography use, including demographics and psychosocial variables. During the year after the receipt of BRCA1/2 test results, 47% of the noncarriers and 59% of the carriers reported that they had had a mammogram [chi(2) (1, n = 107) = 1.35; P = 0.24]. Only 39% of carriers ages 25-39 reported having a mammogram, versus 74% of carriers age > or =40 [chi(2) (1, n = 41) = 5.10; P = 0.02]. Among noncarriers ages 50 and older, 83% had an annual mammogram. Factors independently associated with mammography use included age (<40, > or =40; odds ratio, 7.5; confidence interval, 2.6-21.5) and test result (odds ratio, 4.6; confidence interval, 1.1-18.7). The effects of perceived likelihood of having a BRCA1/2 gene alteration and the interaction between test result and perceived likelihood were not significant. As expected, most carriers (95%) and noncarriers (77%) obtained a clinical breast exam within the year after the receipt of test results. These data suggest that in carriers, overall, the use of breast cancer screening including mammography is good, although there was a relatively low uptake rate of mammography in younger carriers. Noncarriers had very good adherence to general population screening guidelines.