Estimating the cost-effectiveness of flutamide in metastatic cancer

Abstract

The cornerstone therapy for advanced prostate cancer is either surgical castration (bilateral orchiectomy) or medical castration with luteinizing hormone releasing hormone (LHRH) analogues. These therapies are equally effective with about 70% of patients responding. Whether adrenal androgens are an important alternate source of androgen stimulation is controversial. Many clinical trials have been initiated to address the value of maximal or combined androgen blockade using different types of anti-androgens and forms of castration. In the trial that led to the approval of flutamide in the United States of America, Crawford et al. (I) reported a 26% improvement in median survival among men treated with flutamide and leuprolide compared to leuprolide and placebo. Subsequent follow-up of the original report after 77% of all patients had died found a 20% improvement in the median survival (2). Recently, the European Organization for the Research and Treatment of Cancer (EORTC) 30853 trial reported a similar benefit in survival with flutamide (3). Even though these large trials showed a benefit, other investigators have not found similar benefit though these later studies commonly have had methodological flaws. Flutamide has not been widely adopted in America primarily due to drug cost since Medicare does not pay for oral medications. For many men, there is a direct conflict between the immediate out of pocket financial burden and a potential benefit in survial. This report will highlight the findings of a decision analysis model that has been reported elsewhere that estimates the survival, economic impact, and cost-effectiveness of flutamide with orchiectomy or LHRH agonists compared to orchiectomy or LHRH agonists alone for minimal and severe cases of M-l prostate cancer among men with good performance status (4).