Antiandrogen Withdrawal in Treating Patients With Hormone-Refractory Prostate Cancer

OBJECTIVES: I. Compare the response rate and duration of response to antiandrogen withdrawal
alone vs. antiandrogen withdrawal plus ketoconazole/hydrocortisone in patients with advanced
hormone-refractory prostate cancer. II. Compare the response rate and duration of response
to ketoconazole/hydrocortisone in patients treated with previous vs. simultaneous
antiandrogen withdrawal. III. Evaluate the proportion of patients with circulating prostate
cancer cells identified by reverse transcriptase-polymerase chain reaction (rt-PCR). IV.
Determine whether rt-PCR positively correlates with response. V. Compare the likelihood of
response to these regimens in patients whose prior hormonal therapy consisted of initial
combined androgen blockage vs. initial monotherapy followed later by an antiandrogen. VI.
Correlate adrenal androgen synthesis suppression, as measured by levels of various adrenal
androgens, with response.

OUTLINE: Randomized study. Patients who develop progressive disease on Arm I cross to Arm
II. Arm I: Antiandrogen Withdrawal. Antiandrogen stopped. Arm II: Antiandrogen Withdrawal
plus Adrenal Androgen Blockade. Antiandrogen stopped; plus Ketoconazole, KCZ;
Hydrocortisone, HC, NSC-10483.

PROJECTED ACCRUAL: Approximately 250 patients will be entered over 3 years to attain 238
eligible patients (including 25-40 minority patients).

DISEASE CHARACTERISTICS: Histologically diagnosed adenocarcinoma of the prostate
Progressive metastatic or regional nodal disease after at least 4 weeks on flutamide,
bicalutamide, or nilutamide, i.e.: Greater than 25% increase in sum of products of
perpendicular diameters of all measurable lesions not previously irradiated OR
Prostate-specific antigen (PSA) at least 5 ng/mL and risen from baseline on at least 2
successive occasions at least 2 weeks apart PSA progression required for "bone only"
disease or disease that responded to androgen deprivation and is negative on imaging scans
at entry Primary testicular androgen suppression with a luteinizing hormone-releasing
hormone (LHRH) analogue plus antiandrogen or by orchiectomy required Intermittent LHRH
analog/antiandrogen therapy resumed at least 4 weeks prior to and continued at time of
entry LHRH analogue continued throughout study in absence of orchiectomy

PATIENT CHARACTERISTICS: Age: Any age Performance status: 0-2 Hematopoietic: Not specified
Hepatic: Bilirubin no greater than 1.5 times normal AST no greater than 3 times normal
Renal: Not specified Other: No active, uncontrolled condition including: Bacterial, viral,
or fungal infection Hyperglycemia Gastric or duodenal ulcer No existing medical condition
requiring systemic corticosteroids (inhaled and topical steroids allowed) No concurrent
use of the following: Terfenadine Astemizole Cisapride

PRIOR CONCURRENT THERAPY: No prior therapy with experimental agents for metastatic disease
Biologic therapy: No prior immunotherapy for metastatic disease Chemotherapy: No prior
estramustine or other chemotherapy for metastatic disease Endocrine therapy: See Disease
Characteristics No prior hormonal therapy for metastatic disease No prior
aminoglutethimide No prior ketoconazole No prior hydrocortisone or other corticosteroids
Prior experimental hormonal therapy requires approval of study chair Radiotherapy: At
least 4 weeks since radiotherapy (8 weeks since strontium therapy) Surgery: Orchiectomy
allowed