Background: The effect of the palliative irradiation of bone metastases was explored in this retrospective analysis. The spectrum of primary tumor sites, the localization of the bone metastases and the fractionation schedules were analyzed with regard to palliation discriminating total, partial and complete pain response.
Patients and methods: One hundred seventy-six patients are included in this retrospective quantitative study from April 1992 to November 1993. Two hundred fifty-eight localizations of painful bone metastases were irradiated. The percentage of bone metastases of the total irradiated localizations in our department of radiotherapy in the Charité-Hospital, the primary tumor sites, the localizations and the different fractionation schedules were explored. The total, partial and complete pain response was analyzed in the most often used fractionation schedules and by primary tumor sites.
Results: Eight per cent of all irradiated localizations in the observation period were bone metastases. There were irradiated bone metastases of 21 different tumor sites. Most of the primary tumor sites were breast cancer (49%), lung cancer (6%) and kidney cancer (6%). The most frequent site of metastases was the vertebral column (52%). The most often used fractionation schedules were: 4 x 5 Gy (32%), 10 x 3 Gy (18%), 6 x 5 Gy (9%), 7 x 3 Gy (7%), 10 x 2 Gy (5%) and 2 x 8 Gy. The total response rates in this fractionation schedules were 72%, 79%, 74%, 76%, 75% and 72%, the complete response rates were 35%, 32%, 30%, 35%, 33% and 33%. There were no significant differences between the most often irradiated primary tumor sites, the most frequent localizations and the palliation with regard to total, partial and complete pain response.
Conclusion: There are no differences between the different fractionation schedules with regard to the pain effect of bone metastases. A palliation is ensured in 75% of all cases with a partial response of 42% and complete response of 33%. With regard to pain response these results do not justify a recommendation for a standard fractionation schedule. Current fractionation schedules such as 10 x 3 Gy for 2 weeks or 5 x 4 Gy for 1 week should be used. Another point is the recalcification in the palliative treatment of bone metastases in patients with better prognosis. The recalcification is the basis for stabilization and prevention of fractures. This aspect should be explored in prospective studies.