Exploring the accuracy of whole-body MRI in assessing treatment response in metastatic breast cancer: A narrative review

Breast cancer is the second most common cancer worldwide, with metastasis leading to significant morbidity, mortality and healthcare costs. Bone metastasis remains particularly prevalent, estimated to appear in 70 % of cases. Therefore, accurate monitoring of treatment response in metastatic breast cancer is critical. In this review, we advocate for the use of whole-body MRI, which has emerged as a promising alternative to more typical modalities such as CT, PET-CT and bone scintigraphy; this is owed to its high diagnostic accuracy without the need for ionizing radiation or intravenous contrast agents. However, we do acknowledge that challenges persist due to a lack of standardized breast whole body MRI protocols, image reporting criteria, costs, and accessibility issues, limiting its broader implementation. Despite these challenges, MRI's capabilities are expanding, with further research required to establish standardized protocols and validate its use in diverse populations to reinforce whole-body MRI as a preferred imaging modality in metastatic breast cancer. While the future is promising for whole-body MRI, further studies and research will help strengthen the literature base for wider implementation of this modality in regular clinical practice.