Cost-effectiveness of androgen suppression therapies in advanced prostate cancer.
BACKGROUND
The costs and side effects of several antiandrogen therapies for advanced prostate cancer differ substantially. We estimated the cost-effectiveness of antiandrogen therapies for advanced prostate cancer.


METHODS
We performed a cost-effectiveness analysis using a Markov model based on a formal meta-analysis and literature review. The base case was assumed to be a 65-year-old man with a clinically evident, local recurrence of prostate cancer. The model used a societal perspective and a time horizon of 20 years. Six androgen suppression strategies were evaluated: diethylstilbestrol (DES), orchiectomy, a nonsteroidal antiandrogen (NSAA), a luteinizing hormone-releasing hormone (LHRH) agonist, and combinations of an NSAA with an LHRH agonist or orchiectomy. Outcome measures were survival, quality-adjusted life years (QALYs), lifetime costs, and incremental cost-effectiveness ratios.


RESULTS
DES, the least expensive therapy, had a discounted lifetime cost of $3600 and the lowest quality-adjusted survival, 4.6 QALYs. At a cost of $7000, orchiectomy was associated with 5.1 QALYs, resulting in an incremental cost-effectiveness ratio of $7500/QALY relative to DES. All other strategies-LHRH agonists, NSAA, and both combined androgen blockade strategies-had higher costs and lower quality-adjusted survival than orchiectomy. These results were sensitive to the quality of life associated with orchiectomy and the efficacy of combined androgen blockade, and they changed little when prostate-specific antigen results were used to guide therapy. Under a wide range of other assumptions, the cost-effectiveness of orchiectomy relative to DES was consistently less than $20 000/QALY. Androgen suppression therapies were most cost-effective if initiated after patients became symptomatic from prostate metastases.


CONCLUSIONS
For men who accept it, orchiectomy is likely to be the most cost-effective androgen suppression strategy. Combined androgen blockade is the least economically attractive option, yielding small health benefits at high relative costs.
Bayoumi
A M
AM
Department of Medicine, University of Toronto, and Inner City Health Research Unit, St. Michael's Hospital, Toronto, Canada. ahmed.bayoumi@utoronto.ca
Brown
A D
AD
Garber
A M
AM
D000368:Aged; D000726:Androgen Antagonists / Q000191:economics* / Q000627:therapeutic use; D018931:Antineoplastic Agents, Hormonal / Q000191:economics* / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000191:economics / Q000627:therapeutic use; D003362:Cost-Benefit Analysis; D004054:Diethylstilbestrol / Q000191:economics* / Q000627:therapeutic use; D018450:Disease Progression; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists; D006801:Humans; D008297:Male; D008390:Markov Chains; D009364:Neoplasm Recurrence, Local / Q000628:therapy; D009919:Orchiectomy / Q000191:economics*; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000191:economics* / Q000276:immunology / Q000601:surgery / Q000628:therapy*; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States
D000726:Androgen Antagonists; D018931:Antineoplastic Agents, Hormonal; D007987:Gonadotropin-Releasing Hormone; D004054:Diethylstilbestrol; D017430:Prostate-Specific Antigen