[The radiotherapeutic effect on bone metastases in relation to the frequency of metastases, sites of metastases and histology of the primary tumor].

In a retrospective study on 239 patients irradiated for osseous metastases in 578 different skeletal areas, the therapy effect was evaluated in dependence on the frequency of metastases, the sites of metastases, and the histology of the primary tumors. Furthermore the duration of improved findings was verified. The primary tumor was a mammary carcinoma in 186 patients, a bronchial carcinoma in 21 patients, a renal cell carcinoma in 20 patients, and a prostatic carcinoma in 12 patients. In patients with bronchial carcinoma the relief of pain by radiotherapy was not as good as in other tumor types. However, a significant correlation between subjective therapy effect and histology of the primary tumor was not demonstrated. Remineralization was found in 55% of all irradiated skeletal areas and an unchanged X-ray picture of bone metastases in 35%. A dependence of the objective therapy effect from the histology of the primary tumor was not statistically demonstrated (recalcification rate in mammary carcinoma 62%, in prostatic carcinoma 57%, in bronchial carcinoma 28%, and in renal cell carcinoma 11%). Significant differences of remineralization were found in solitary bone metastases (68%) and in multiple skeletal metastases (56%). A significant correlation between sites of metastases and objective irradiation effect was proved by the fact that osteolytic destructions of spine and pelvis showed a better remineralization than lesions situated in the extremities. The average duration of the objective, radiologically verified amelioration of findings was 16 months in patients with mammary carcinomas and 12 months in patients with prostatic carcinomas, bronchial carcinomas, and renal cell carcinomas.