Economic consequence of local control with radiotherapy: cost analysis of internal mammary and medial supraclavicular lymph node radiotherapy in breast cancer.

Abstract

To investigate the financial implications of radiotherapy (RT) to the internal mammary and medial supraclavicular lymph node chain (IM-MS) in postoperative breast cancer. A cost-effectiveness and cost-utility analysis were performed, using Markov models, comparing the early and delayed costs and effects of IM-MS during a 20-year time span from a societal viewpoint. The outcome estimates were based on Level I evidence from postoperative RT literature and the cost estimates on the standard practice of the Leuven University Hospitals, with the RT costs derived from an activity-based costing program developed in the department. On the basis of the assumptions of the model and seen during a 20-year time span, primary treatment including IM-MS RT results in a cost savings (approximately 10,000) compared with a strategy without RT. Because IM-MS RT also results in better clinical effectiveness and greater quality of life, the treatment with IM-MS dominates the approach without IM-MS. Sensitivity analyses confirmed the robustness of these results in all tested circumstances. Although threshold values were found for the cost of IM-MS, the cost at relapse, and the quality of life after treatment, these were substantially different from the baseline estimates, indicating that it is very unlikely that omitting IM-MS would become superior. This ex-ante cost evaluation of IM-MS RT showed that the upfront costs of locoregional RT are easily compensated for by avoiding the costs of treating locoregional and distant relapse at a later stage. The cost-sparing effect of RT should, however, be evaluated for a sufficiently long time span and is most specifically found in tumors with a rather slow natural history and a multitude of available systemic treatments at relapse, such as breast cancer.