Antiandrogens alone or in combination for treatment of prostate cancer: the European experience

Long-term outcome of antiandrogen monotherapy in advanced prostate carcinoma: 12-year results of a phase II study

OBJECTIVE

To present the long-term outcome of patients with locally advanced or metastatic prostate carcinoma treated by first-line antiandrogen monotherapy.

PATIENTS AND METHODS

From 1983 to 1990, 41 patients with advanced prostate carcinoma were treated with flutamide monotherapy until progression or the appearance of toxicity. Twenty-five patients (61%) had T3-T4N0M0 and 16 (39%) T2-4N0-3M1 prostate carcinoma. Consensus criteria were adopted to evaluate the response. Plasma testosterone and sexual function were recorded for the first 3 years.

RESULTS

Flutamide was administered for up to 147 months; seven patients (17%) interrupted the treatment because of toxicity. There was an objective response in 17 (41%) patients; 20 (49%) had stable disease while four (10%) progressed. There were objective responses, lasting up to 150 months, in 82% of those with M0 and in 18% with M1 disease (P = 0.05). The median time to progression in patients with an objective response and stable disease was 45 and 16 months, respectively (P < 0.001). Thirty-one patients (76%) died from prostate cancer and 10 (24%) from unrelated diseases. The median survival was 67 and 36 months in patients with an objective response and stable disease, respectively (P < 0.001). There was an improvement in performance status in 85% and reduction in bone pain in 83% of the patients; sexual activity was maintained in 63%.

CONCLUSION

Monotherapy with flutamide is well tolerated. Objective responses are more frequent in patients with locally advanced disease. Patients with an objective response within 6 months have a prolonged progression-free and overall survival.

Treatment changes in prostatic hyperplasia and cancer, including androgen deprivation therapy and radiotherapy

Substantial and characteristic changes occur in the microscopic appearance and immunophenotype of the hyperplastic prostate and adenocarcinoma following androgen deprivation therapy and radiotherapy. These changes are rarely seen in untreated cancer, and in the authors' opinion, the combinations of features following therapy are sufficiently distinctive to warrant recognition. Pathologists must be aware of these distinct changes because of the reliance placed on nuclear and nucleolar size in the identification of prostate cancer, particularly in small specimens and lymph node metastases.

A double-blind, placebo-controlled, crossover trial of an antiandrogen in the treatment of Tourette's syndrome

The objective of this study was to document the effects of androgen receptor blockade on tic and obsessive-compulsive symptoms in Tourette's syndrome (TS) patients. Thirteen adult TS subjects, 10 men and 3 women, completed 3 weeks of each phase of a double-blind, placebo-controlled, crossover trial of flutamide, a selective androgen receptor antagonist. Symptom severity ratings and hormone levels were obtained at each of the trial's six clinic visits. Flutamide was well-tolerated and produced a significant reduction in motor but not phonic tic symptom severity. It modestly improved symptoms of obsessive-compulsive disorder in the men who had this disorder. Changes in hormone levels during flutamide administration provided evidence for the existence of physiologic mechanisms that compensate for the blocking of the androgen receptor. The therapeutic effects of flutamide are modest in magnitude and they seem to be short-lived, possibly because of physiologic compensation for androgen receptor blockade. Given the potentially serious side effects of flutamide, the use of this agent in the treatment of tics should be reserved for patients who have relatively debilitating symptoms. The therapeutic and endocrine findings may have implications for understanding the sex differences in TS prevalence and the sex-specific variability in the phenotypic expression of the putative TS vulnerability genes.

Hormone therapy for prostate cancer: a topical perspective

Evolution of the roles proposed for antiandrogenic agents in prostatic disease has been rapid. Since the early suggestions by Labrie and his colleagues that the nonsteroidal antiandrogen flutamide could be used in combination with medical or surgical castration to provide superior care for patients with metastatic prostate cancer, and subsequent substantiation of the theory in a number of clinical trials, we have observed an increasing tendency to test the use of antiandrogens (alone or in combination with other interventions) earlier in the disease process. At least in part, this tendency is a consequence of our increased ability to detect prostate cancer earlier in the disease process. At the present time, flutamide is the only nonsteroidal antiandrogen available for the treatment of prostate cancer in general clinical practice in the United States. However, two other nonsteroidal antiandrogens currently await decisions on their efficacy and safety by the Food and Drug Administration: nilutamide and bicalutamide. Will either of these agents offer clinical benefits beyond those offered by flutamide? Will the safety, activity, and dosing profiles of the nonsteroidal antiandrogens allow us to use them to treat even earlier stages of prostate cancer and perhaps even prostatic intraepithelial dysplasia in patients at high risk of prostate cancer? What are the potential future roles for bicalutamide and other nonsteroidal antiandrogens in the management of prostatic disorders? This article will attempt to lay out the key questions that await definitive answers as we expand our understanding of the possible future roles for antiandrogens in the management of prostate cancer and related conditions.