Availability Versus Utilization of Supplemental Breast Cancer Screening Post Passage of Breast Density Legislation.

Objective: Despite the lack of evidence that supplemental screening in women with dense breasts reduces breast cancer mortality, 38 states have passed breast density legislation, with some including recommendations for supplemental screening. The objective of this study is to compare the availability versus use of supplemental breast cancer screening modalities and determine factors driving use of supplemental screening in rural versus urban settings. Methods: A 50-item mailed survey using the Tailored Design Method was sent to American College of Radiology mammography-accredited facilities in North Carolina in 2017. Respondents included 94 facilities (48 rural and 46 urban locations). Survey questions focused on breast cancer and supplemental screening services, breast density, risk factors/assessment, and facility demographics. Results: The survey response rate was 60.3% (94/156). Among the 94 respondents, 64.0% (n = 60) reported availability of any type of supplemental screening (digital breast tomosynthesis [DBT], ultrasound, or magnetic resonance imaging [MRI]). In facilities where supplemental screening modalities were available, the most commonly utilized supplemental screening modality was DBT (96.4%), compared with ultrasound (35.7%) and MRI (46.7%). Facilities reported using supplemental screening based on patient breast density (48.3%), referring physician recommendation (63.3%), reading radiologist recommendation (63.3%), breast cancer risk factors (48.3%), and patient request (40.0%). Urban facilities were more likely than rural facilities to base supplemental screening on breast cancer risk factors (62.5% vs. 32.1%; p-value = 0.019), referring physician (75.0% vs. 50.0%; p-value = 0.045), and reading radiologist (78.1% vs. 46.4%; p-value = 0.011). Conclusion: In our study, supplemental screening modalities were widely available, with facilities more likely to use DBT for supplemental screening compared to other modalities.