Half body irradiation (HBI) in metastatic carcinomas.

One hundred and twenty-nine patients with distressing pain due to widespread bony metastases have been treated by systemic radiation therapy. The response rate is very high (76%) and the relief of pain occurs dramatically within 24-48 h. Sixty-five per cent of all responders remained free from pain for the remainder of their liver (3-10 months). This treatment has also proved effective in reducing large tumour masses for a limited period of time (5-20 weeks). Effective control of resistant hypercalcaemia was also observed within 24 h in five patients out of nine. The treatment is well tolerated and is haematologically safe. The main limiting factor is pulmonary damage. Various corrective measure have been employed to reduce acute radiation toxicity. This report presents an up to date analysis of the response to, and toxicity of, systemic radiation therapy and speculates on its potential uses.