High resolution DBT exams enhance early cancer detection
Compared to standard options, high resolution digital breast tomosynthesis exams enhance detection of breast cancer, especially when prior films are available for review.
The emergence of DBT has significantly improved breast cancer detection rates, especially in women with dense breasts. However, there is room for improvement, and recent advances in imaging technology have built on the momentum DBT utilization has created.
In 2018, new detector and image processing technology that increased image resolution from 100 μm pixel size (standard resolution) to 70 μm pixel size (high resolution) was approved for commercial use. High resolution (HR) imaging technology is said to enhance the visualization of tumor margins and subtle distortions and improve the visibility of small micro-calcifications. However, there is limited research on how HR compares to standard resolution (SR) in terms of cancer detection rates, recall rates and positive predictive value in real-world settings.
The authors of a new paper in Clinical Imaging sought to address this issue with their latest analysis.
“With the introduction of any new breast screening technology, it is important to evaluate the impact on real world clinical outcomes,” Melinda Talley, MD, a radiologist at Sanford Health, in Sioux Falls, South Dakota, and colleagues noted.
To get a better understanding of the added value of HR breast cancer screening exams, researchers recently conducted a thorough analysis of more than 180,000 screenings that took place before and after the introduction of HR technology. The team examined the effect of SR and HR on cancer detection rates, recall rates and positive predictive value, also taking note of how the availability of prior imaging taken with more outdated technology impacted these metrics.
Of the 184,006 mammograms included in the analysis, 95,633 were in SR, while 88,373 were captured in HR. Positive predictive values were similar in both groups, but recall rates were slightly higher in the HR cohort. However, the researchers suggested that the increase in recall rates may be transient when considering how prior advances in imaging initially impacted patient recalls.
“A transient increase in recall is consistent with previous advances in mammography,” the group explained. “For example, previous studies reported an increase in recall rates for women receiving their first digital mammogram, while the recall rates for women receiving subsequent digital mammograms was similar to the rates with film mammography.”
The cancer detection rate for HR was higher than those in the SR cohort, at 5.38 per 1,000 exams compared to 4.87 per 1,000. After adjusting for age, race, density, risk status, prior resolution, facility and radiologist, the team determined that the difference in detection rates was statistically significant. These figures improved for HR even more when patients had prior imaging that radiologists could use for comparison.
Though the difference may seem small at first glance, the team described the increase in detection rates as “notable,” as it likely leads to earlier diagnoses and, therefore, improved outcomes for patients.
Learn more about the team’s findings here.
In addition to her background in journalism, Hannah also has patient-facing experience in clinical settings, having spent more than 12 years working as a registered rad tech. She began covering the medical imaging industry for Innovate Healthcare in 2021.