A Case of a Concurrent and Co-Located Invasive Carcinoma and a Fibroadenoma to Illustrate the Potential of Dual-Energy, Contrast-Enhanced Digital Mammography on the Diagnosis of Complex Breast Lesions

Up to 19% of breast malignancies may be missed by conventional imaging techniques, especially when they are concurrent or co-located with other benign lesions. However, more sensitive techniques, such as magnetic resonance imaging (MRI), are often too expensive for routine use in developing countries. Contrast-enhanced, dual-energy digital mammography (CESM) is a recently introduced imaging modality whose performance has been reported to be similar to that of MRI. Being much cheaper, CESM may constitute a good alternative for improving diagnostic sensitivity in these countries. In this paper, we present a challenging case of the concurrent and co-located presentation of a fibroadenoma and a triple negative invasive carcinoma of no special type (TNBC-NST). The malignancy was indistinguishable from the fibroadenoma by mammography. By ultrasound, a suspicious area was observed and biopsied, but the histopathology did not confirm a cancer diagnosis. As the suspicion was not confirmed, a second stage of the imaging diagnosis using CESM was recommended. This technique allowed clear visualization of the malignancy, which was finally excised by breast-conserving surgery. This case reveals the potential of CESM as an easy, rapid and inexpensive new technique for the diagnosis of malignancies that might easily remain occult to mammography plus breast ultrasound (BUS).