Flutamide Eliminates the Risk of Disease Flare in Prostatic Cancer Patients Treated with a Luteinizing Hormone-Releasing Hormone Agonist

Abstract

Although chronic treatment with luteinizing hormone-releasing hormone agonists achieves castration levels without side effects other than those related to hypoandrogenism, a limitation to their use alone for the treatment of prostatic cancer is the transient increase in serum androgens that lasts for 5 to 8 days at the start of treatment with the risk of disease flare. Our data show that the concomitant administration of the pure antiandrogen flutamide in association with the luteinizing hormone-releasing hormone agonist (D-Trp6) luteinizing hormone-releasing hormone ethylamide caused a 64 to 78 per cent decrease in serum prostatic acid phosphatase on days 3 to 7 after the start of treatment in 70 patients with previously untreated stage D2 prostatic cancer. Pain, which was present in 41 patients at the start of treatment, did not increase in any patient, it decreased in 7 at 1 week and it disappeared or decreased in 27 at 2 weeks. Performance, which originally was abnormal in 34 patients, became normal in 7 within 1 week and in 20 within 1 month (59 per cent). These data show that the addition of flutamide completely eliminates the risks of disease flare associated with the use of the otherwise exceptionally well tolerated luteinizing hormone-releasing hormone agonists in patients treated for prostatic cancer.