A review of local radiotherapy in the treatment of bone metastases and cord compression.

Local radiotherapy plays an important role in the management of bone metastases. Because it is given with palliative intent to patients with limited, if variable, life expectancy, radiotherapy schedules need to be identified which give maximum patient benefit (short and long term) with minimum associated morbidity and minimum disruption of the patients' remaining life. For localized bone pain, a single fraction of radiotherapy, repeated if necessary, appears to fulfill these criteria in patients with a short life expectancy. There are, however, unanswered questions regarding fraction size and the adequacy of one fraction for long-term control and for all pathological tumor types. Only randomized trials can answer these questions. Uncertainties also exist regarding the precise indications for radiotherapy to prevent and treat pathological fractures and the optimal dose schedule which will provide adequate local tumor control without inhibiting bone healing or interfering with bone integrity. Because of the many variables, guidelines on selection of cases of spinal cord compression for decompression by surgery or radiotherapy are likely to be of more value than randomized prospective studies in this condition. Experimental work and clinical experience to date suggest an advantage for a few large fractions of radiotherapy, at least initially, to achieve a rapid response, but this too needs confirmation. Treatment decisions based on past teaching and local custom rather than on valid clinical trial data have led to considerable differences in clinical practice among radiotherapists. Bone metastases are common and warrant a great deal more experimental and clinical study than they have received to date.