Automated breast ultrasonography (ABUS) among women with BRCA1 and BRCA2 mutation may not be of added value to yearly full-field digital (FFD) mammography and dynamic contrast agent–enhanced (DCE) MR imaging, according to a study published in Radiology.
Researchers from the Netherlands performed a prospective trial to evaluate the surveillance regimen including yearly FFD mammography, DCE MR imaging, and biannual ABUS in women with BRCA1 and BRCA2 mutations.
A total of 296 carriers of the BRCA mutation were enrolled in the study between September 2010 and November 2012, with follow-up until November 2015; 153 women were BRCA1 carriers, 128 were BRCA2 carriers, and 15 women had first-degree untested relatives. All women underwent two years of intensified surveillance that included biannual AB US, and routine yearly DCE MR imaging and FFD mammography.
The results showed that breast cancer was detected through screening in 16 women, ranging in age from 33 to 58. Of four cancers found in BRCA1 carriers, three were interval cancers detected by self-examination (all three women were under 43), and one because of a palpable abnormality in the contralateral breast. One incidental breast cancer was detected in a prophylactic mastectomy specimen.
|MR Imaging||FFD Mammography||ABUS|
|Sensitivity||68.1% (14 of 21)||37.2% (eight of 21)||32.1% (seven of 21)|
|Specificity||95.0% (643 of 682)||98.1% (638 of 652)||95.1% (1030 of 1088)|
|Cancer detection rate (per 100 women years)||2.0% (14 of 702)||1.2% (8 of 671)||1.0% (7 of 711)|
|Positive predictive value||25.2% (14 of 54)||33.7% (9 of 23)||9.5% (7 of 68)|
DCE MR imaging and FFD mammography combined yielded the highest sensitivity of 76.3% (16 of 21) and specificity of 93.6% (643 of 691). ABUS did not depict additional cancers; FFD mammography yielded no additional cancers in women younger than 43, the mean age at diagnosis.
Among the women who carried the BRCA2 mutation, sensitivity of FFD mammography with DCE MR imaging surveillance was 90.9% (10 of 11) and 60.0% (six of 10) in carriers of the BRCA1 mutation because of the high interval cancer rate in carriers of the BRCA1 mutation.
The researchers concluded that routinely adding ABUS to yearly screening of women with the BRCA mutation did not add value.