A Model of the Cost-effectiveness of Intensity-modulated Radiotherapy in Comparison with Three-dimensional Conformal Radiotherapy for the Treatment of Localised Prostate Cancer

Aims: To determine the cost-effectiveness of intensity-modulated radiotherapy (IMRT) compared with three-dimensional conformal radiotherapy (3DCRT) for men with localised prostate cancer from a UK National Health Service perspective. Materials and methods: A discrete event simulation model was developed to simulate the progress of patients through advancing disease states until death from prostate cancer or other causes. Clinical effectiveness data for IMRT and 3DCRT were derived from a systematic review. Four scenarios were modelled based on different clinical studies. A probabilistic sensitivity analysis was undertaken and the incremental cost per quality adjusted life years (ICER) calculated. Results: In scenarios where estimated survival was greater for IMRT than 3DCRT, IMRT was clearly cost-effective (ICER <20 pound 000). For scenarios where only a difference in late gastrointestinal toxicity was assumed, the ICER was highly sensitive to uncertain model parameters, including the magnitude of the difference, the duration of gastrointestinal toxicity and the cost difference between treatments. For the most likely scenario, a 15% difference in late gastrointestinal toxicity, the ICER was 35 pound 000, with a 20% probability that it is cost-effective at a maximum threshold of 20 pound 000 and a 48% probability at a threshold of 30 pound 000. Conclusion: If IMRT can be used to prolong survival, it is very cost-effective. Otherwise cost-effectiveness is uncertain. (C) 2012 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.