Men whose metastatic prostate cancer is maintained in remission by complete hormonal therapy (CHT) with flutamide(Drug information on flutamide) (Eulexin) and a luteinizing-hormone-releasing hormone (LHRH) agonist have a health-related quality of life (QOL) equal to that of a matched population of men in the general population, according to a study published in the February issue of Urology (49:207-217, 1997).
"The goals of treating metastatic prostate cancer are to increase longevity and maintain a high quality of life. Now we have evidence that treatment with Eulexin and an LHRH agonist can accomplish both of these goals," said Peter C. Albertsen, md, of the Division of Urology at the University of Connecticut Health Science Center, Farmington, lead author of the report.
The American Cancer Society (ACS) estimates that 334,500 men will be diagnosed with prostate cancer in 1997. Prostate cancer is the second leading cause of cancer death in American men and will claim some 41,800 lives this year. According to the ACS, some 42% of prostate cancer cases are diagnosed in either locally advanced or metastatic stages. In addition, many patients initially treated for early-stage prostate cancer later experience a recurrence, with metastatic disease.
Control of metastatic prostate cancer is based on depriving the tumor of the growth-promoting effects of androgens, of which the principal one is testosterone. Flutamide, an antiandrogen, acts by directly blocking the effects of these hormones. Complete hormonal therapy combines flutamide with an LHRH agonist to inhibit cancer growth by maximizing androgen blockade.
Studies Show Benefits of Complete Hormonal Blockade
Although, at present, metastatic prostate cancer cannot be cured, several major studies have shown the value of CHT. One was a large National Cancer Institute study comparing complete hormonal blockade with an LHRH analog plus flutamide vs the LHRH analog alone in more than 600 patients with stage D2 prostate cancer (N Engl J Med 321:419-424, 1989). Median overall survival was significantly longer in patients receiving CHT with flutamide than in those given only the LHRH agonist (34.9 vs 27.9 months); also, progression-free survival was prolonged by 2.6 months (19%) in the patients given the combination therapy (Eulexin product information, Schering Corporation, Kenilworth, New Jersey, June 1996).
In this study, side effects of the LHRH agonist included hot flashes, loss of sex drive, impotence, breast enlargement. and nausea. The only additional side effect reported by patients in the CHT group was diarrhea (12%, vs 4% in those given the LHRH agonist alone). Hepatic injury occurred in fewer than 1.0% of patients receiving combined hormonal blockade.
New Study Measures More QOL Factors
Dr. Albertsen and his colleagues evaluated the health-related QOL (HRQL) of 60 patients with metastatic (stage D2) prostate cancer in remission and 53 patients whose stage D2 disease was progressing. All patients were given an LHRH agonist and flutamide. In addition, the investigators compared the QOL of the cancer patients in remission with that of men in the general US population matched for age and sociodemographic criteria.
Previous QOL studies have been limited to such measurements as pain scares and performance status. The new study was the first to measure the impact on QOL of such disease- or treatment-related effects as diarrhea, constipation, nausea, vomiting, weight gain or loss, urinary symptoms, sexual function, and hot flashes and such equally important QOL indicators as social interactions, mental health, vitality, and sexual satisfaction.
In this study of 113 patients, there were no HRQL differences between the cancer patients in remission and men in the general population. Not surprisingly, however, the men whose prostate cancer was progressing had a significantly lower QOL in several areas--bodily pain, vitality, social interactions, and mental health--than did those who were in remission. In fact, the investigators' analysis showed that the reduction in HRQL of prostate cancer patients in general is entirely attributable to the lower QOL among those with progressive disease.
"Before making treatment decisions, cancer patients and health care payers alike are increasingly demanding evidence that treatments have a positive impact on their quality of life as well as their survival," Dr. Albertsen said. "We now know that when patients respond, CHT with Eulexin provides meaningful benefits on both counts."
Since 1989, flutamide has been marketed in the United States by Schering Corporation as part of CHT for the treatment of advanced (stage D2) prostate cancer. In June 1996, flutamide received marketing clearance for use, in combination with an LHRH agonist, as neoadjuvant therapy in conjunction with radiation therapy for locally confined (stage B2-C) prostate cancer.