RATIONALE: Doxercalciferol may be an effective way to treat localized prostate cancer before surgery.

PURPOSE: Randomized phase II trial to study the effectiveness of giving doxercalciferol before surgery in treating patients who have localized prostate cancer.

OBJECTIVES:

• Determine whether doxercalciferol modulates intermediate endpoint biomarkers in the development of prostate cancer in patients with localized prostate cancer.
• Assess the toxicity of this drug in these patients.

OUTLINE: This is a randomized, open-label, multicenter study. Patients are randomized to one of 2 arms.

• Arm I: Patients receive doxercalciferol once daily for 28 days. Patients then undergo prostatectomy.
• Arm II: Patients undergo observation for 28 days. Patients then undergo prostatectomy.

PROJECTED ACCRUAL: A total of 60 patients (30 per arm) will be accrued for this study within 18 months.

DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed localized adenocarcinoma of the prostate
• Candidate for prostatectomy

PATIENT CHARACTERISTICS:

Age:

• 21 and over

Performance status:

• Not specified

Life expectancy:

• Not specified

Hematopoietic:

• WBC at least 4,000/mm^3
• Platelet count at least 100,000/mm^3

Hepatic:

• Bilirubin no greater than 1.4 mg/dL
• AST no greater than 3 times normal

Renal:

• Creatinine no greater than 2.0 mg/dL
• Calcium no greater than 10.2 mg/dL
• No idiopathic urinary calcium stone disease

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• Not specified

Endocrine therapy:

• No prior hormonal therapy for prostate cancer
• No concurrent hormonal therapy, including luteinizing hormone-releasing hormone agonists, antiandrogens, glucocorticoids, ketoconazole, finasteride, diethylstilbestrol, or progestins

Radiotherapy:

• No prior brachytherapy or external beam radiotherapy for prostate cancer

Surgery:

• See Disease Characteristics

Other:

• At least 7 days since prior vitamin D therapy or calcium supplements
• No other concurrent vitamin D analogues or calcium supplements
• No concurrent magnesium-containing antacids
• No concurrent thiazide-containing diuretics
• No concurrent phenytoin, phenobarbital, glutethimide, digoxin, or digitalis