A model for decision making for the use of radiotherapy in lung cancer.

To develop an evidence-based benchmark for the use of radiotherapy in lung cancer, we did a systematic review of treatment guidelines on radiotherapy for lung cancer. We then constructed an optimum use of radiotherapy "tree" from epidemiological data, which shows the proportion of patients with clinical attributes indicating that they would benefit from radiotherapy. We calculated that the proportion of patients with lung cancer in whom radiotherapy is indicated (according to the best available evidence) is 76%. We then compared this ideal rate with the actual rates of use of radiotherapy for lung cancer in Australia, and internationally, in the past decade. A substantial discrepancy was found between the evidence-based recommended rate of use and the actual rates reported in clinical practice. We hope this model will be used to plan efficient and cost-effective radiotherapy services.