Research Summary

Abbreviated MRI and Contrast-Enhanced Mammography Outperform ABUS in Women With Dense Breasts, Negative Mammogram

Anthony Calabro, MA

Key Highlights

  • Abbreviated MRI and contrast-enhanced mammography each detected ~3x more invasive cancers than automated breast ultrasound (ABUS).
  • Median tumor sizes were 10-11 mm for contrast-enhanced methods, compared with 22 mm for ABUS.
  • Higher recall and biopsy rates were observed with contrast-enhanced imaging than with ABUS.

In this interim analysis of the Breast screening—Risk Adapted Imaging for Density (BRAID) randomized controlled trial, abbreviated MRI and contrast-enhanced mammography both significantly outperformed automated breast ultrasound (ABUS) in detecting additional breast cancers in women with dense breast tissue and a negative mammogram. The cancer detection rates were 17.4 and 19.2 per 1000 examinations for abbreviated MRI and contrast-enhanced mammography, respectively, compared with 4.2 per 1000 for ABUS. Invasive cancers detected by contrast-based methods were also smaller, with a median size of 10-11 mm compared with 22 mm with ABUS.

Mammographic screening in dense breast tissue is known to have reduced sensitivity, leading to increased risks of interval cancers and later-stage diagnosis. Despite global recognition of this risk, no consensus exists on the optimal supplemental imaging strategy. The BRAID trial fills a critical gap by directly comparing three supplemental modalities—abbreviated MRI, ABUS, and contrast-enhanced mammography—in a randomized cohort of average-risk women in the UK National Health Service (NHS) Breast Screening Program.

Between October 2019 and March 2024, 9361 women aged 50 to 70 years with heterogeneously or extremely dense breasts and a negative screening mammogram were randomized across 10 NHS centers. Of these, 6305 women completed supplemental imaging. Imaging protocols were standardized and centrally evaluated. The primary outcome was the rate of histologically confirmed breast cancer. Secondary endpoints included recall and biopsy rates, tumor characteristics, and adverse events.

Abbreviated MRI and contrast-enhanced mammography each identified 32 invasive cancers, while ABUS identified nine. Only the contrast-enhanced techniques detected ductal carcinoma in situ. Recall rates for abbreviated MRI and contrast-enhanced mammography were 9.7%, compared with 4.0% for ABUS. Biopsy rates were also higher in the contrast-enhanced groups. Despite slightly increased adverse event profiles—particularly in the contrast-enhanced mammography group—serious complications were rare.

The current study had limitations. For example, the trial lacked long-term data on interval cancers and mortality. Additionally, there were challenges in directly comparing all four arms due to logistics. Finally, the study also went through protocol deviations including delayed imaging beyond 6 months for some participants.

“This study shows that contrast-enhanced techniques such as abbreviated MRI and contrast-enhanced mammography have a superior performance compared with whole breast ultrasound,” the authors concluded. “This is in line with systematic reviews of performance, although no other study has directly compared these techniques in the same cohort of average-risk women. The information in this trial will allow sophisticated modelling to estimate the cost benefit of implementing a supplemental imaging strategy.”

Reference
Gilbert FJ, Payne NR, Allajbeu I, et al. Comparison of supplemental breast cancer imaging techniques—interim results from the BRAID randomised controlled trial. Lancet. 2025;405(10322):1935-1944. doi:10.1016/S0140-6736(25)00582-3