Stereotactic radiotherapy for bone oligometastases.

About 60-90% of cancer patients are estimated to develop bone metastases, particularly in the spine. Bone scintigraphy, computed tomography (CT ) and magnetic resonance imaging (MRI ) are currently used to assess metastatic bone disease; positron emission tomography/computed tomography (PET-CT ) has become more widespread in clinical practice because of its high sensitivity and specificity with about 95% diagnostic accuracy. The most common and well-known radiotracer is 18F-fluorodeoxyglucose (FDG); several other PET-radiotracers are currently under investigation for different solid tumors, such as C or FDG-choline and prostate specific membrane antigen (PSMA)-PET/CT for prostate cancer.