Radiopharmaceuticals for bone lesions - Imaging and therapy in clinical practice

Bone scintigraphy continues to be one of the most commonly performed proced ures in nuclear medicine. The radionuclide bone scan remains an excellent m odality to detect metastatic disease in patients suffering from primary mal ignancies. This article reviews a number of aspects of bone scintigraphy su ch as bone physiology, radiopharmaceuticals and uptake mechanisms. As Tc-99 m labelled bis(di)phosphonates are the most frequently used this articke is centred around these imaging agents. In addition to diagnostic bone scinti graphy the use of various bone seeking agents has been extended to the pall iative treatment of bone metastases. In this context the radiobiological ch aracteristics of various radionuclides as Sr-89, P-32, Sm-153, Re-186 and S n-117 is elucidated. In addition, the clinical efficacy for pain killing of these radionuclides is elucidated on the basis of the radiation properties of these agents. It is concluded that Sr-89 and Re-186 are presently the r adionuclides of choice. The latter agent has a slight advantage as its imag ing photons enable individual dosimetry, resulting in an optimosed applicat ion scheme.