Breast cancer screening: Evidence of the effect of adjunct ultrasound screening in women with unilateral mammography-negative dense breasts

Background: Patients with the previous history of breast cancer are in risk of contralateral breast cancer. On the other hand, increased breast density is a risk factor for breast cancer and the sensitivity of detecting nonpalpable cancers in screening mammography in radiographically dense breasts is low. The use of ultrasonography in dense breast remains a controversial topic. The purpose of this study was to assess the usefulness of routine ultrasonography in follow-up of women with the previous history of breast cancer and negative mammography but dense breasts. Materials and Methods: In a cross-sectional study, a total of 267 individuals with unilateral postmastectomy mammogram screened and 153 subjects assigned to study. There were 28 subjects with American College of Radiology (ACR) breast density 2 and 125 with ACR breast density 3-4, which there was no new finding in their mammogram in comparison to previous studies. We assumed subjects with ACR breast density 3-4 as mammographic Breast Imaging Reporting and Data System (BI-RADS) category 0 for malignancy. Standard two-view mammogram was performed for all participants, and breast ultrasound (US) examinations were performed by an expert radiologist in radial and anti-radial planes. The data were analyzed using SPSS version 20.0 (SPSS Inc., Chicago, Illinois, USA). Results: The results showed that in subjects with ACR breast density 3-4, when there was no new density in two consecutive mammograms in comparison to previous studies, US also showed no possibility for malignancy (BI-RADS 1-2). And also in subjects with ACR breast density 2, when the mammographic results were BI-RADS 1-2, the US results was the same. Conclusion: Our data indicate that for the detection of breast cancer, sensitivity of US was not greater than mammography in patients with postmastectomy unilateral dense breast if there is not any new density.