American College of Radiology criticizes prominent study pushing for new approach to breast cancer screening

The American College of Radiology is criticizing prominent research pushing for a new approach to breast cancer screening. 

Published Friday in the Journal of the American Medical Association, scientists recently explored a risk-based mammography tactic that tailors regular imaging regimens to each individual’s danger of developing the disease. This would have some high-risk women receiving screening every six months, while others would wait until age 50 to start regular screening, instead of 40, as ACR recommends.

“Risk-based breast cancer screening is safe and acceptable, offering an opportunity to modernize screening in the precision medicine era,” lead author Laura J. Esserman, MD, MBA, with the University of California, San Francisco, and colleagues wrote Dec. 12 in JAMA.

However, ACR poked holes in the study, which is part of the WISDOM (Women Informed to Screen Depending on Measures of Risk) randomized clinical trial comparing different imaging approaches. The college noted there was “substantial nonadherence” among the study’s participants, “making it difficult at best to determine the impact of screening.” 

“The ACR thanks WISDOM Trial researchers for attempting to determine whether risk-based breast cancer screening is a feasible alternative to annual mammography as the healthcare community works toward optimal breast cancer screening approaches,” the college said in a statement issued Dec. 12. “However, the study design and results do not provide adequate information to support changes to present screening policies.”

More on the original research

Esserman and co-authors’ analysis compared risk-based screening provided to over 14,000 randomly assigned women against regular annual screening provided to another 14,000 who served as the control group. The study recruited women ages 40 to 74, without prior diagnoses of breast cancer or double mastectomies, across all 50 states between 2016 and 2023.

Based on genetic assessments determining their susceptibility to the disease, women in the risk-based group received 1 of 4 different tailored recommendations. Those at the highest risk, for instance, underwent alternating mammography and MRI every six months, alongside counseling. Meanwhile, those at “elevated risk” of breast cancer received annual mammography and risk-reduction counseling. Others at average risk of developing the disease had mammography every other year. And finally, those at low risk and in their 40s received no screening until either the genetic risk increased to 1.3%, or they reached the age of 50. 

Tracking the results over a median of 5.1 years, Esserman et al. found that risk-based screening was “noninferior” compared to the traditional time-based approach. “Importantly,” women in the highest risk category, assigned to screen every six months, had no stage 2B or worse breast cancer cases. However, the risk-based approach did not reduce breast biopsy rates. Plus, rates for cancer detection, biopsy and mammograms increased with rising risk in the key study group.

“The WISDOM study demonstrated that a risk-based approach successfully stratifies the population for breast cancer risk and is safe and acceptable to women,” Esserman and co-authors concluded. “Development of better risk models and risk-reducing recommendations hold promise for future improvements, as does more effective risk communication to patients and healthcare professionals to promote informed, shared decision-making.” 

ACR’s response

However, ACR criticized these conclusions in its response shared Friday. It noted that the annual and risk-based study groups had nearly identical, low rates of mammography use, noting the “study is not truly comparing different imaging scenarios.” Plus, no group actually had an annual mammogram over the study period, and MRI use was low in the highest risk group. This resulted in an average of less than one MRI after seven years, “and occurred outside the trial in other groups,” ACR wrote.

The WISDOM trial only recorded outcomes for stage 2B or higher cancers, which are about 1 inch in diameter and likely already present on breast exams. Thus, the benefit of early detection via annual mammography, finding cancers before visible signs emerge, is “essentially eliminated from trial documentation.” ACR also noted that the trial required intense breast health specialist interventions with patients, which “may be difficult to replicate in many clinical settings.” Still, even with this intensified approach, the study produced “poor adherence to risk reduction strategies.” 

“This trial has not proven the approach to be better than current recommendations,” the college wrote. “The ACR continually gathers and reviews peer-reviewed studies and data from multiple sources to determine when—and how often—screening approaches may need to be updated,” it added later. 

Two physician editorialists called the WISDOM trial an “important study,” which established that risk-based breast cancer screening recommendations “can be made at scale.” However, they acknowledged some of the same shortcomings as ACR, with screening itself performed outside of the study’s parameters and substantial nondadherence in both cohorts.

“Further analysis of trial results, including patient-reported outcomes and cost, will help place results in context, and evidence from ongoing trials, including the My Personalized Breast Screening (MyPeBS) and Tailored Screening for Breast Cancer in Premenopausal Women trials, will help inform practice,” Australian physicians Nancy N. Baxter, MD, PhD, and Kelly Anne Phillips, MD, wrote Friday. “However, to fully realize the potential for breast cancer control through risk-based screening, purposeful integration with prevention is needed.”