Palliative radiotherapy to the chest is often used in patients with lung cancer, but radiotherapy regimens are more often based on tradition than research results.

To discover the most effective and least toxic regimens of palliative radiotherapy for non-small cell lung cancer, and whether higher doses increase survival.

The electronic databases MEDLINE, EMBASE, Cancerlit and the Cochrane Central Register of Controlled Trials, reference lists, handsearching of journals and conference proceedings, and discussion with experts were used to identify potentially eligible trials, published and unpublished.

Randomised controlled clinical trials comparing different regimens of palliative radiotherapy in patients with non-small cell lung cancer.

Fourteen randomised trials were reviewed. There were important differences in the doses of radiotherapy investigated, the patient characteristics and the outcome measures. Because of this heterogeneity no meta-analysis was attempted.

There is no strong evidence that any regimen gives greater palliation. Higher dose regimens give more acute toxicity, especially oesophagitis. There is evidence for a modest increase in survival (5% at 1 year and 3% at 2 years) in patients with better performance status (PS) given higher dose radiotherapy. Some regimens are associated with an increased risk of radiation myelitis.

The majority of patients should be treated with short courses of palliative radiotherapy, of 1 or 2 fractions. Care should be taken with the dose to the spinal cord. The use of high dose palliative regimens should be considered for and discussed with selected patients with good performance status. More research is needed into reducing the acute toxicity of large fraction regimens and into the role of radical compared to high dose palliative radiotherapy. In the future, large trials comparing different RT regimens may be difficult to set up because of the increasing use of systemic chemotherapy. Trials looking at how best to integrate these two modalities, particularly in good PS patients, need to be carried out.