Chapter 10 - Screening for Breast Cancer in Women With Dense Breasts

Abstract

High breast density or dense breasts is a common risk factor for breast cancer that increases the false-negative and false-positive rate of mammography. Supplemental screening in women with dense breasts and a negative screening mammogram may facilitate early cancer detection and reduce mortality from breast cancer. This chapter reviews the literature on the test characteristics and clinical outcomes of supplemental screening of women with dense breasts with the four most commonly used modalities: hand-held ultrasound, automatic breast ultrasound, breast magnetic resonance imaging (MRI), and digital breast tomosynthesis (DBT). Ultrasound identifies an additional 2–3 cancers per 1000 women screened, but has a high recall rate and benign biopsy rate, and a low positive predictive value for cancer following biopsy (PPV3 ~7%). The data for breast MRI primarily reflect studies in very high-risk women. It has the highest cancer detection rate and maintains a PPV3 of about 25%, which is comparable to that of mammography overall; however, the technology is invasive, time-consuming, and costly for widespread use in the general population. DBT holds promise as a replacement of digital mammography for primary screening, but has limited data available addressing its effectiveness at reducing interval cancer rates in women with dense breasts. The rate of additional cancers detected by DBT is similar to ultrasound, but it has a much lower recall rate and a PPV3 of about 25% in women with dense breasts. No studies demonstrated a reduction in breast cancer mortality or the incidence of advanced stage breast cancer. Risk assessment can be used to target supplemental screening to those who have the most potential to benefit.