[Percutaneous radiotherapy of bone metastases]

Bone metastases causing pain syndromes and imminent pathologic fractures are among the main reasons for radiotherapy in patients suffering from malignant tumors. The indication is much influenced by the radiologic findings. Surgical methods are to be chosen in the first place in cases of pathologic fractures or patients with a high risk of such fractures. Different authors recommend various therapeutic regimens. Effective pain control can be achieved with one single dose of radiation. Doses of 6 to 40 Gy applied in one to 19 days are also efficient. Side effects, especially nausea and vomiting occur in 25% of cases; this number rises to 50% in cases of half body irradiation. Visible changes of bone mineral density may be noticed about 6 weeks after termination of radiotherapy. About 70% of osteolytic metastases show progressive sclerosis whereas osteosclerotic lesions may show both increase or decline of bone mass. In spite many years of experience the optimal strategy for radiation therapy of bone metastasis has not been defined; further studies are needed.