Adding ultrasound to mammography increases false-positive findings without an increase in cancer detection

Reference

Lee JM, Arao RF, Sprague BL, et al. Performance of screening ultrasonography as an adjunct to screening mammography in women across the spectrum of breast cancer risk. JAMA Intern Med 2019;179(5):658-667.

Synopsis

These researchers compared the results from 6081 women who were screened for breast cancer with mammography and ultrasound with 30,062 screening mammograms from 15,176 women drawn from 13 years of data from 2 breast cancer surveillance registries in the United States. Most (74.3%) of the ultrasound screens were performed in women with dense breasts, and, as compared with the mammography-alone group, were more likely to be at higher risk of breast cancer or to be younger than 50 years. Despite these differences, the cancer detection rate was similar across groups (5.4 vs 5.5 per 1000 screens), as was the development of cancer between screenings (interval cancer rate). However, the rate of unnecessary biopsies was more than twice as high for the combination screening (52.0 vs 22.2 per 1000 screens), as were calls for rescreening at shorter-than-normally-recommended intervals (relative risk = 3.10; 95% CI 2.6 - 3.7).