Screening for Breast Cancer with Contrast-enhanced Mammography as an Alternative to MRI: SCEMAM Trial Results

Abstract

Background Many state laws require insurance coverage for supplemental screening MRI in women at elevated risk for breast cancer, but MRI capacity is limited. Purpose To evaluate the impact of contrast-enhanced mammography (CEM) on incremental cancer detection rate (ICDR), false-positive rate (FPR) due to recall, and positive predictive value of biopsies performed (PPV3) when added to digital breast tomosynthesis (DBT) in women eligible for screening MRI. Materials and Methods From March 2021 to December 2022, 615 eligible women were prospectively recruited and consented to a single screening CEM examination with clinical DBT. Two radiologists interpreted each imaging study: Reader 1 recorded DBT findings first, and reader 2 recorded CEM findings first. Incremental cancer detection rate, cancer type and/or nodal status, FPR, PPV3, interval cancer rate, and areas under receiver operating characteristic curve (AUCs) based on forced Breast Imaging Reporting and Data System assessments were evaluated. Results Six hundred one women (mean age, 56 years [range: 30-75 years]) completed CEM. Twelve of the 601 women (2.0%) were diagnosed with 16 malignant lesions; cancers in five of the 12 women (42%) were detected by reader 1 at DBT, and one was detected at DBT by reader 2 (also seen on CEM by both observers). Cancers in the other six women were identified only with CEM (ICDR, six per 601 or 10.0 per 1000 women [95% CI: 3.3, 18.3]): five had invasive disease, all node negative, with a median lesion size of 0.7 cm (range: 0.4-1.1 cm); three were lobular. The FPR of combined DBT plus CEM was 127 of 589 (21.6%) for reader 1, which was an increase of 13.4% (95% CI: 10.8, 16.4) over DBT alone at 48 of 589 (8.1%). Despite increased FPR, the addition of CEM improved the overall AUC for reader 1 to 0.92 versus 0.73 for DBT alone (P = .016). Among the 601 women, 50 (8.3%) were recommended for biopsy according to CEM by reader 1, and six of the 50 (12%) were diagnosed with cancer. At the lesion level, the PPV3 was seven of 62 (11%) for biopsies prompted only with CEM by reader 1. There were no interval cancers at 1 year. Conclusion A significant increase in the detection of early-stage breast cancer was achieved using CEM after DBT. Despite substantially increasing the FPR, adding CEM to DBT improved the overall AUC by 0.19. ClinicalTrials.gov registration no.: NCT04764292 © RSNA, 2025 Supplemental material is available for this article.