Going for a bone scan. ct showed 2 tiny sclerotia lesions on spine. with history of breast cancer. does scan show cancer and/or arthritis? does it know the difference?

A good test: Bone scans are used in patients with localized bone pain or an elevated alkaline phosphatase (a blood test) to rule out breast cancer localized in the bone. The test is good in differentiating malignant (i.e. cancer) vs. benign conditions (i.e. arthritis). If the bone scan is negative and clinical suspicion warrants further evaluation, MRI could be performed, too.