Laws that only require women to be told they have dense breasts, without any further information, don’t seem to make a difference in extra screenings or cancers detected, the study team reports in American Journal of Public Health.
Roughly half of U.S. women in their 40s and 50s have dense breast tissue, which increases their risk of breast cancer and makes it harder to detect tumors with mammography. Several states require healthcare providers to send notification letters to women whose mammograms show dense breast tissue. Some states also require that these higher-risk women be advised to get screened with ultrasound or magnetic resonance imaging (MRI), which can better detect tumors in dense breast tissue.
A new proposal from the U.S. Food and Drug Administration, announced March 27, would require all mammography facilities in the U.S. to include breast density information in letters to patients. For the current study, researchers examined data on screening and cancer diagnoses for more than 1.4 million women ages 40 to 59 in nine states with dense breast notification laws and 25 states without these laws.
“We found that dense breast notification laws were associated with small increases in cancer detection” said lead study author Susan Busch of the Yale School of Public Health in New Haven, Connecticut.
“This effect was only found in states with laws that included language about the benefits of supplemental testing,” Busch said by email.”We did not have enough follow-up data to take the next step and determine whether dense breast notification laws were associated with reduced breast cancer mortality.”