8570 Background: For selected patients with MESCC, S + RT has recently been shown to improve patients’ ability to ambulate and reduce opioid and corticosteroid use when compared with RT alone, with a trend towards survival benefit. (Patchell et al Lancet 2005) The economic impact of adopting this intervention has not been assessed previously. Methods: An analytic decision model was constructed based on the results from Patchell et al. (2005) The perspective of the public health care insurer of Ontario was adopted for the analysis. Costing was performed by using Ontario data for the following items: surgery, radiotherapy, hospitalization, home care services, palliative hospice, and medications. Utilities were obtained from the Harvard University Catalogue of preference score (HUC) and the Health Outcomes Data Repository Data - Health Utility list (HODaR). The primary analysis is a cost-utility analysis comparing surgery and radiotherapy (S+RT) with radiotherapy alone (RT). A probabilistic sensitivity analysis with Monte-Carlo simulation was performed. Results: When comparing S+ RT with RT alone, the incremental cost-effectiveness ratio (ICER) is CAD$ 43,796 per QALY gained. The cost-utility of S + RT is CAD$ 509,084 per QALY and that of RT alone is CAD$ 2,381,246 per QALY. S + RT costs approximately CAD$ 33 more when compared with RT alone per ambulatory day gained. The cost of surgery is partially offset by the decreased cost of hospice palliative care since more patients remain ambulatory and stay at home. Monte-Carlo simulation showed that there is a 25% chance that S + RT may dominate RT alone. The results are sensitive but generally robust to changes in assumptions about the costs of surgery, home care and palliative hospice care. Conclusions: S+RT is likely cost-effective when compared with RT alone for the treatment of MESCC in selected patients, and should be considered by health care policy makers. No significant financial relationships to disclose.