THE ROLE OF LOCAL RADIOTHERAPY IN THE TRE ATMENT OF BONE METASTASES

Local radiotherapy plays an important role in the palliative managemen t of bone metastases. Different concepts of dose fractionation are in use. A judgement of the efficacy of these concepts should be based on their different palliative treatment endpoints. The efficacy of radiot herapy using published data can be analysed with respect to pain relie f and re-establishment of bone integrity as treatment endpoints. Trial s stratifiying radiooncological techniques according to an optimizatio n of quality of life are missing. Nevertheless, the rationale for indi vidual treatment in daily work is based on systemic tumor extent, life expectancy, the kind of symptoms and the location of the metastasis i n question. In patients with reduced live expectancy a remarkably high chance of pain relief (70 %) could be achieved with single doses of 8 Gy. The latency period until pain relief is shorter with higher singl e doses. In case of recurrence of pain reirradiation with a single dos e results in an equally high response rate. Patients with a solitary m etastasis, patients with longer live expectancy and patients with path ological fractures should be treated with 'curative' doses, aimed to c ause maximum tumor cell killing. Impaired bone stability in patients w ho are not suitable for surgical intervention requires orthetic supply . Apart from the effect of pain relief, remineralization is the import ant treatment goal for these patients. Conventional radiotherapy with doses of 40-50 Gy resulted in remineralization in 60-80 % of the patie nts 4-8 weeks after irradiation. Remineralization could not be acceler ated by short course fractionation courses.