GADOLINIUM-BASED AND IODINATED CONTRAST AGENTS IN BREAST IMAGING: CHALLENGES AND NEW TRENDS

Purely morphological imaging modalities such as digital mammography and breast ultrasound still represent the backbone of breast imaging. However, a sizable diagnostic gain can be granted by functional information and improved tissue characterization coming from the analysis of the uptake of contrast agents in the breast. Since the advent of contrast-enhanced breast imaging in 1986, contrast-enhanced breast magnetic resonance imaging (CE-MRI), involving the administration of gadolinium-based contrast agents, has been the chief morphofunctional breast imaging modality. Conversely, contrast-enhanced mammography (CEM, a dual-energy X-ray-based technique where iodinated contrast agents are administered) began to emerge in the research and clinical scenarios of breast care only in the early 2000s. From 2015 onwards, applications of CEM saw a rapid expansion and began to challenge CE-MRI, also considering the emergence of unexpected concerns about late adverse effects of the administration of gadolinium-based contrast agents. The first section of this thesis presents an appraisal of the risk-benefit balance of the administration of gadolinium-based contrast agents in screening and diagnostic breast imaging, alongside the results of a dose-reduction study for preoperative CE-MRI. The second section presents research related to CEM, incorporating the two largest available systematic reviews on its technical aspects and on its diagnostic performance, the first multicenter study on CEM radiation dose, and the first prospective study on CEM potential use to decrease the rate of unnecessary breast biopsies.