“Adding annual CEM to digital breast tomosynthesis (DBT) in women with PHBC substantially increased early cancer detection. … The low cancer yield at DBT, which was only 3.8 per 1000 in incident years (years 2 and 3), suggested that some of the cancers that usually would have been seen were detected in the prior year at CEM,” wrote lead study author Wendie Berg, M.D., Ph.D., a professor of radiology at the University of Pittsburgh School of Medicine, and colleagues.
Three Key Takeaways
- Enhanced detection of second malignancies. Combining contrast-enhanced mammography (CEM) with digital breast tomosynthesis (DBT) led to increased detection of second malignancies in women with a history of breast cancer compared to DBT alone. This is particularly significant for early detection and management of recurrent breast cancer.
- Improved diagnostic performance. The addition of CEM to DBT resulted in higher sensitivity, as indicated by a higher area under the curve (AUC) throughout the study, with a 21 percent higher sensitivity rate (93 percent vs. 72 percent) in comparison to DBT alone for the second and third years of the study. Researchers also noted eight invasive cancers detected only with CEM were 1 cm or smaller.
- Recall rates and screening efficacy. Although the combination of CEM/DBT initially showed higher recall rates compared to DBT alone in the first year, recall rates declined for both approaches in subsequent years. Despite higher recall rates initially, the combination approach led to improved cancer detection without sacrificing sensitivity over time, supporting its potential as an supplemental screening method for women with a personal history of breast cancer.
The researchers noted that of the 18 breasts that had CEM-only detected lesions, 72 percent were invasive, and 50 percent were in women with dense breasts. The study authors also found that CEM was more effective at diagnosing smaller breast cancer lesions.
“The median invasive tumor size of the largest cancer for each breast was 6 mm (range, 1–21 mm) for those seen only at CEM and 9 mm (range, 1–18 mm) for those seen at both DBT and CEM,” pointed out Berg and colleagues. “Eight of the invasive cancers seen only at CEM were 1 cm or smaller and node negative (five of these had pathologic nodal staging, and three were clinically node negative), representing a 73% increase in the detection of such tumors from 11 seen at DBT to 19 after adding CEM.”
(Editor’s note: For related content, see “Is Contrast-Enhanced Mammography a Viable Option for Diagnosing Invasive Lobular Carcinoma?,” “Study: Contrast-Enhanced Mammography Changes Surgical Plan in 22.5 Percent of Breast Cancer Cases” and “Mammography Study: AI Improves Breast Cancer Detection and Reduces Reading Time with DBT.”)
Recall rates were higher with the combination of CEM/DBT in the first year of the study (14.7 vs. 8.1 for DBT alone) but the researchers noted recall declines for both approaches in the second (9.0 vs. 3.9) and third years (7.9 vs. 3.5).
“Our interim results, while preliminary, support the use of CEM for annual supplemental screening in women with PHBC,” added Berg and colleagues.
In regard to study limitations, the authors acknowledged the possibility of patient selection bias contributing to the high breast cancer yield in the first year of the study. Noting that the research was performed at multiple facilities within one health care system, the researchers conceded that broader extrapolation of the study findings may be limited. They also said that a lack of prospective reporting of low-energy findings and related recalls prohibited evaluation of standalone CEM specificity.
