OBJECTIVES: We performed a pharmacoeconomic evaluation of LHRH agonists (LAs) in treating metastatic prostate cancer compared to standard care, as identified in the literature and by clinical experts, including estrogens (DES), orchiectomy, antiandrogens (AAs), and combinations therapy (LAs+AAs). METHODS: A Markov model was constructed to perform a cost-effectiveness analysis (CEA) over 5 years, from a Canadian provincial healthcare payer perspective. Efficacy of treatments was determined by meta-analysis of clinical data. RESULTS: In the base case analysis, DES was least costly at $588, but also the least effective, with 1.11 expected life-years (ELYs). The cost of orchiectomy was $830 with a greater effectiveness of 1.71 ELYs, and an incremental cost effectiveness ratio of $399/Life Year Gained (LYG) over DES. AAs or LAs resulted in higher costs, $4,108 and $8,116 respectively, but lower effectiveness of 1.19 ELYs and 1.50 ELY respectively, thus were both dominated by orchiectomy. LAs+AAs was most costly at $18,029, but with the highest effectiveness (1.89 ELYs), with an incremental cost effectiveness ratio of $97,301/LYG over orchiectomy. Changes in key-parameters in sensitivity analyses did not affect the ranking of the treatment strategies, suggesting that the model was robust. CONCLUSIONS: LAs were dominated by orchiectomy in the base case analysis and most sensitivity analyses. Combination therapy displayed incremental cost effectiveness ratios over orchiectomy ranging from approximately $30,000 to $100,000 per LYG. Orchiectomy was more effective, had fewer severe adverse reactions, and cost slightly more than DES, the least expensive treatment. However, due to potential psychological impact, further research is warranted to examine its acceptance by patients.