Abstract

Breast cancer (BC) imaging spans screening, diagnosis, local staging, treatment assessment, surveillance, and detection of recurrence or metastasis. Because these tasks are not addressed equally well by a single technique, imaging in BC has developed as a multimodality, indication-based practice. This review synthesizes how mammography, ultrasound, MRI, CT, and PET/CT are positioned across the BC care continuum and where their evidence base is strongest in relation to specific clinical questions. This narrative review drew on English-language literature identified through searches of MEDLINE/PubMed, Embase, Scopus, Web of Science Core Collection, and the Cochrane Library. Searches were conducted between December 2025 and March 2026 and focused on evidence from the preceding 20 years, supplemented by citation tracking of reviews, guidelines, and consensus statements. Mammography remains the only breast imaging modality supported by population-level evidence for mortality reduction and continues to anchor screening and surveillance. Ultrasound is central to symptomatic assessment, biopsy guidance, and axillary triage, with a selective role in supplemental screening. MRI provides the highest sensitivity for selected screening settings, extent assessment, and post-neoadjuvant evaluation. CT and PET/CT are primarily systemic imaging tools; routine staging in asymptomatic stage I–II disease and routine surveillance after curative treatment are not supported, whereas PET/CT has its clearest value in higher-risk staging, suspected recurrence, and selected response-assessment settings. BC imaging is best understood as a complementary, indication-driven strategy in which modality selection depends on the clinical question, baseline risk, and expected impact on management.