Not All Bone Lesions After Breast Cancer Treatment Indicate Metastasis: A Case Report and Review of the Literature

Breast cancer is one of the osteophilic cancers. However, the appearance of bone-related symptoms in a pretreated patient is not always indicative of bone metastases. We report a case of a patient pretreated for localized breast cancer who subsequently developed bone symptoms, with lytic bone lesions on spinal MRI, which were ultimately found to be related to multiple myeloma. This clinical case outlines the diagnostic difficulties of multiple myeloma in patients with a history of breast cancer, highlighting the risk of delayed multiple myeloma management.