Valproic Acid in Treating Patients With Progressive, Non-Metastatic Prostate Cancer

You may be eligible if

• DISEASE CHARACTERISTICS:
• Histologically confirmed prostate cancer
• * Asymptomatic, non-metastatic disease
• Biochemical progression after definitive local therapy (radical prostatectomy)
• * Most recent prostate-specific antigen (PSA) level ≥ 1.0 ng/mL AND rising over the prior value
• * No clinical or radiological evidence of local progression
• PSA doubling time (DT) \< 10 months after local therapy (in patients who have not received prior hormone therapy)
• * At least three PSA values (each at least 4 weeks apart) are required to calculate the PSA-DT
• No clinical or radiological evidence of metastatic disease, including bone metastasis
• PATIENT CHARACTERISTICS:
• ECOG performance status 0-2
• Life expectancy \> 3 months
• Total bilirubin normal
• AST/ALT \< 2.5 times upper limit of normal
• Creatinine ≤ 2.5 mg/dL
• Platelet count \> 125,000/mm\^3
• PT and aPTT ≤ 1.3 times above the standard reference
• Albumin ≥ 3.5 g/dL
• Geographically accessible and willing to participate in all stages of study treatment
• No active second malignancy
• No known HIV positivity
• No active, uncontrolled infection (e.g., hepatitis A, B, or C infection)
• No history of allergic reactions attributed to compounds of similar chemical or biological composition to valproic acid
• No debilitating medical or psychiatric illness that would preclude giving informed consent or receiving optimal study treatment and follow-up
• No history of hepatic disease or significant hepatic dysfunction
• No history of pancreatitis
• No history of seizure disorder or clinically treated bipolar disorder
• PRIOR CONCURRENT THERAPY:
• More than 6 months since prior hormone therapy
• No prior valproic acid
• At least 2 weeks since prior drugs specifically known to interact with valproic acid including, but are not limited to, aspirin, felbamate, rifampin, amitriptyline/nortriptyline, carbamazepine, clonazepam, diazepam, ethosuximide, lamotrigine, phenobarbital, primidone, phenytoin, tolbutamide, warfarin, or zidovudine
• No concurrent systemic chemotherapy for prostate cancer
• No other concurrent investigational drugs