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Member Research & Reports

Member Research & Reports

Yale: Researchers Find Breast Ultrasound and Cancer Detection Increased Under New Laws

State breast density notification laws that mandate reporting of mammogram results can prompt further screening and modestly boost cancer detection rates, say researchers at Yale’s School of Public Health and School of Medicine. The study was published in the American Journal of Public Health.

About half of women in the United States in their 40s and 50s have dense breast tissue, which increases their risk of breast cancer and make it harder to detect cancer on a mammogram. In response to these concerns, many states now require healthcare providers to notify women about if they have dense breasts after they undergo mammography. However, in recent years, some states have gone a step further, mandating that these notifications also include recommendations that women with higher breast density should consider supplemental screening tests, such as ultrasound and magnetic resonance imaging (MRI).

To investigate whether these different types of state laws affect patterns of screening, researchers analyzed data from more than one million  mammograms provided to privately insured women in their 40s and 50s. The women lived in states with either no notification law, a law that only included information about their breast density status, or a law that also recommended supplemental tests. The research team analyzed whether the type of law made a difference in clinical practice — specifically rates of breast ultrasound and cancer detection.

The research team found that women living in states with laws recommending supplemental screening tests had increased rates of breast ultrasound and cancer detection after the law was implemented. In contrast, the researchers found no changes in clinical practice related to notifications that only included information about breast density.