Contrast-associated risks of iodine-based contrast media administration in breast imaging: Tips and overview of existing evidence - A narrative review.

[BACKGROUND] Contrast-enhanced mammography (CEM) and dedicated breast computed tomography (dBCT) are advanced breast imaging techniques that utilize iodine-based contrast media (ICM) to improve the visualization of tumor vascularity. This review explores key challenges related to ICM use in these imaging modalities, focusing on hypersensitivity reactions (HR), acute kidney injury (AKI), and risk screening.

[METHODS] A narrative review was conducted to summarize the available evidence based on guidelines, recommended questionnaires, and relevant recent research. A literature search using PubMed and Embase identified guidelines on the safe use of ICM from January 2017 to February 2025, along with studies on CEM and dBCT. Keywords included (synonyms of) "iodine-based contrast media," "hypersensitivity reactions to ICM," "kidney function tests," "contrast-associated acute kidney injury," "contrast-induced acute kidney injury," and "contrast-enhanced mammography," "dedicated breast CT." Guidelines related to subspecialties, intra-arterial contrast administration, and outdated versions were excluded.

[RESULTS] Nine guidelines from international medical and radiological associations were included. While the majority of evidence comes from studies on contrast-enhanced computed tomography (CECT), the findings are applicable to CEM and dBCT as they use similar non-ionic low-osmolar ICM. HR with ICM is rare (0.3 %-0.7 %) but can be severe, with some requiring treatment (e.g., H1-antihistamines or intramuscular adrenaline). Any patient experiencing a mild HR should be observed for at least 30 min after administration. AKI occurs in at least 5 % of cases, which may rise to 30 % in patients with chronic kidney disease (CKD). Current guidelines suggest targeted testing for CKD risk using patient questionnaires, which is applicable to breast imaging, given the low prevalence of advanced CKD in this population.

[CONCLUSION] ICM risks in breast imaging are similar to CECT but tend to occur less often due to the lower-risk, non-urgent outpatient population. Both HR and AKI are infrequent, and at-risk patients can be identified through questionnaires.