BACKGROUND: Potential harms of screening mammography include false positive results, such as recall breast imaging or biopsies.
METHODS: We recruited women undergoing screening mammography at Columbia University Medical Center in New York, New York. They completed a questionnaire on breast cancer risk factors and permitted access to their medical records. Breast cancer risk status was determined using the Gail model and a family history screener. High risk was defined as a 5-year invasive breast cancer risk of ≥1.67% or eligible for BRCA genetic testing. False positive results were defined as recall breast imaging (BIRADS score of 0, 3, 4, or 5) and/or biopsies that did not yield breast cancer.
RESULTS: From November 2014 to October 2015, 2,361 women were enrolled and 2,019 were evaluable, of whom 76% were Hispanic and 10% non-Hispanic white. Fewer Hispanic women met high-risk criteria for breast cancer than non-Hispanic whites (18.0% vs. 68.1%), but Hispanics more frequently engaged in annual screening (71.9% vs. 60.8%). Higher breast density (heterogeneously/extremely dense vs. mostly fat/scattered fibroglandular densities) and more frequent screening (annual vs. biennial) were significantly associated with false positive results [odds ratio (OR), 1.64; 95% confidence interval (CI), 1.32-2.04 and OR, 2.18; 95% CI, 1.70-2.80, respectively].
CONCLUSIONS: We observed that women who screened more frequently or had higher breast density were at greater risk for false positive results. In addition, Hispanic women were screening more frequently despite having a lower risk of breast cancer compared with whites.
IMPACT: Our results highlight the need for risk-stratified screening to potentially minimize the harms of screening mammography.