Structural racism, within and beyond health care, may increase the likelihood that Black, Hispanic/Latina and Asian American women experience significant delays more commonly than white women in getting breast biopsies after a mammogram identifies an abnormality.

UC Davis cancer researcher Diana Miglioretti, who helped lead a study that was published in the journal JAMA Oncology, said the findings show that interventions are needed to reduce cultural barriers to timely diagnosis after abnormal mammogram results. Miglioretti is a professor and the chief of the Department of Public Health Sciences’ Division of Biostatistics.

“Unfortunately, our research shows that Black women were the most likely to experience delays in diagnostic resolution after adjusting for multilevel factors,” said Miglioretti, who collaborated with Michael Bissell, also with UC Davis’ biostatistics division. Other key researchers on the study included lead author Marissa Lawson and senior author Christoph Lee, both from the University of Washington.

The study reviewed the cases of 45,186 women whose screening mammograms had shown a tissue abnormality that called for a biopsy to ascertain whether it was cancerous. Across the study population, 34.6% of women were not biopsied within 30 days, 16% were not biopsied at 60 days, and 12% were not biopsied within 90 days.

“The delays are concerning because previous studies have indicated that the benefit of screening diminishes with time, and these lags are associated with later-stage disease at time of diagnosis,” Miglioretti said.

Using the time-to-biopsy of white patients as the benchmark, the researchers found that:

  • At 30 days out, Asian women had a 66% higher risk of not undergoing a biopsy, Black women, 52% higher, and Hispanic/Latina women, 50% higher.
  • At 90 days out, Black women had a 28% higher risk of not undergoing a biopsy. Among Asian women and Hispanic/Latina women, the risk was 21% higher and 12% higher, respectively.

With that unadjusted model, the researchers then examined whether specific factors of individual patients, their neighborhoods and their screening facilities influenced the time to biopsy among women of different races and ethnicities.

“Controlling for individual- and neighborhood-level factors, we saw that risk was not very different from the unadjusted model,” Lawson explained. “But when we controlled for the screening facility attended, delays in time to biopsy were reduced.”

Digging deeper, the investigators examined the influence of predesignated site-level factors — academic affiliation, screening-exam modality and the availability of onsite biopsy — and were surprised to find that none of those factors explained the overt difference.

“The findings indicate that there are some differences among the screening facilities associated with the time to biopsy. We just don’t know what the specific differences are,” Lawson said.

The screening sites are all associated with the Breast Cancer Surveillance Consortium, a U.S. network of breast imaging registries that is representative of the country’s population in terms of age, race and ethnicity.

The study’s authors encourage radiology departments to consider using navigators to help guide patients through the process of scheduling exams and procedures, as a means of reducing wait times for biopsies.