Perifosine in Treating Patients With Metastatic, Androgen-Independent Prostate Cancer

DISEASE CHARACTERISTICS: Histologically confirmed adenocarcinoma of the prostate, meeting all of the following criteria: Metastatic Androgen-independent Progressive disease while continuing to receive hormonal ablation (e.g., luteinizing hormone-releasing hormone [LHRH] agonist) Progression documented by at least 1 of the following parameters: Two consecutively rising prostate-specific antigen levels, at least 1 week apart, with at least 1 measurement that is 50% above the nadir reached after the last treatment regimen (as long as the last measurement is at least 5 ng/mL) At least 1 new metastatic lesion on technetium Tc 99m bone scintigraphy Progression of soft-tissue metastases as measured by appropriate modalities (i.e., imaging or palpation) and demonstrated by at least 1 of the following: Development of new area of malignant disease (measurable or nonmeasurable) At least a 20% increase in the sum of the longest diameters (LD) of target lesions from the smallest sum of LD recorded since the treatment started or the appearance of 1 or more new lesions Patients who have not undergone surgical castration must have a testosterone level less than 50 ng/mL and continue on their LHRH agonist during study treatment No known brain metastases PATIENT CHARACTERISTICS: Age 18 and over Performance status ECOG 0-2 OR Karnofsky 60-100% Life expectancy More than 3 months Hematopoietic WBC at least 3,000/mm^3 Absolute neutrophil count at least 1,500/mm^3 Platelet count at least 100,000/mm^3 Hepatic Bilirubin less than 1.0 mg/dL or upper limit of normal (ULN) AST/ALT no greater than 2.5 times ULN Renal Creatinine no greater than 1.5 mg/dL OR Creatinine clearance at least 60 mL/min Cardiovascular No myocardial infarction within the past 6 months No unstable or newly diagnosed angina pectoris No New York Heart Association class II-IV congestive heart failure Ophthalmic No pre-existing retinal disease No pathologic baseline electrooculogram Other Fertile patients must use effective barrier contraception Able to ingest oral medication No prior allergic reactions attributed to compounds of similar chemical or biological composition to perifosine (e.g., miltefosine or edelfosine) No ongoing or active infection No other concurrent uncontrolled illness No psychiatric illness or social situation that would preclude study compliance No other active malignancies within the past 2 years except nonmelanoma skin cancer or carcinoma in situ of the bladder PRIOR CONCURRENT THERAPY: Biologic therapy Not specified Chemotherapy No more than 1 prior chemotherapy regimen More than 4 weeks since prior chemotherapy (at least 6 weeks for nitrosoureas or mitomycin) Endocrine therapy See Disease Characteristics More than 4 weeks since prior flutamide More than 6 weeks since prior bicalutamide or nilutamide Radiotherapy At least 6 weeks since prior bone-seeking radioisotopes Recovered from prior radiotherapy Surgery See Disease Characteristics Recovered from prior surgery Other Recovered from any acute toxicity related to prior therapy More than 3 months since prior UCN-01 More than 3 months since prior suramin No concurrent commercial or other investigational agents or therapies intended to treat the malignancy No concurrent combination antiretroviral therapy for HIV-positive patients