Contrast-Enhanced Spectral Mammography in Women With Intermediate Breast Cancer Risk and Dense Breasts

Objective: The purpose of this study was to compare the diagnostic performance of contrast-enhanced spectral mammography (CESM) and ultrasound with that of standard digital mammography for breast cancer screening of women at intermediate risk who have dense breasts.

Materials and methods: In a retrospective cohort of 611 consecutively registered women who underwent screening CESM from 2012 to 2017, BI-RADS scores of the screening modalities were compared with actual disease status, assessed by histopathologic analysis or imaging follow-up. Sensitivity, specificity, and positive and negative predictive values were calculated.

Results: Among the 611 women included, 48.3% (295/611) had family or personal history of breast cancer, the BI-RADS breast density score was C or D in 93.1% (569/611). The mean follow-up period was 20 months. Mammography depicted 11 of 21 malignancies, sensitivity of 52.4%, specificity of 90.5% (534/590), positive predictive value of 16.4% (11/67), and negative predictive value of 98.2% (534/544). CESM depicted 19 of 21 malignancies, sensitivity of 90.5%, specificity of 76.1% (449/590), positive predictive value of 11.9% (19/160), and negative predictive value of 99.6% (449/451). Differences in sensitivity (p = 0.008) and specificity (p < 0.001) were statistically significant. Adjunct ultrasound revealed 73 additional suspicious findings; all were false-positive. In 39 women MRI was needed to assess screening abnormalities; two MRI-guided biopsies were performed and yielded one cancer. The incremental cancer detection rate of CESM was 13.1/1000 women (95% CI, 6.1-20.1). Of eight cancers seen only with CESM, seven were invasive (mean size, 9 mm; two of four cancers lymph-node positive).

Conclusion: CESM was significantly more sensitive than standard digital mammography for detecting breast cancer in this screening population. No added benefit was found in the performance of ultrasound as an adjunct to CESM screens with negative results. CESM may be a valuable supplemental screening modality for women at intermediate risk who have dense breasts.