Inclusion Criteria:

Patients must have a histologically or cytologically confirmed history of adenocarcinoma
of the prostate

Patients must have a PSA failure defined as PSA of >= 0.2 ng/ml that has increased above
nadir following prostatectomy

If radiation or other local therapy was used as a primary therapy and no prostatectomy was
performed patients must have PSA increase of 2.0 above post-therapy nadir; PSA value must
be increasing based on two consecutive measurements each separated by at least 2 weeks
with no clinical or radiographic evidence of metastatic disease; PSA values that meet the
criteria for eligibility within 4 weeks of registration are acceptable to document
eligibility for enrollment on this study; PSA level obtained after registration and prior
to the first course will be used as the "baseline" PSA as per the schema but will not
determine eligibility for participation

Patients must have had at least three PSA measurements over a minimum of three months
available prior to enrollment to this study

Patients may have received any number of local therapies (radical prostatectomy, external
beam radiation therapy, radioactive seed implantation, cryotherapy)

Bone scan and computed tomography (CT) scan of the chest, abdomen and pelvis negative for
metastatic disease within 2 months prior to registration

Patients must have a performance status of 0, 1, or 2

All patients will have malignancy confirmed by review of their biopsy specimens by the
Division of Pathology, City of Hope National Medical Center; if no pathological specimen
is available for review, the patient may still be included if the patient has clearly
documented prostate cancer per pathology report and a specimen request is documented as
having been made for tissue from the outside facility but a specimen was unable to be
obtained

Serum creatinine =< 2.5 mg/dL

Baseline liver function tests including bilirubin =< 1.5 x the institutional upper limit
of normal and serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic
transaminase (SGPT) =< 2.5 x the institutional upper limit of normal

White blood cells (WBC) >= 2000

Platelets >= 50,000

Exclusion Criteria:

Patients with evidence of metastatic disease PSA progression not verified by sequential
rising PSA as discussed in the eligibility section

Patients who have received prior cytotoxic chemotherapy or androgen ablative therapy for
recurrent disease

Patients currently receiving biological response modifiers, or corticosteroids

Patients are permitted to have received up to 24 months of neoadjuvant or adjuvant hormone
ablation in conjunction with their primary definitive therapy; androgen deprivation must
have been completed at least 6 months prior to registration and testosterone level must be
> 50; no complementary or alternative therapy (e.g. St. John's Wort, PC-SPES, or other
herbal remedies taken for the purpose of treating prostate cancer) may be given during
protocol treatment; patients are allowed to have received neoadjuvant and/or adjuvant
chemotherapy that was completed at least 6 months prior to registration to the protocol

Uncontrolled intercurrent illness including, but not limited to, ongoing active infection,
symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or
psychiatric illness/ social situations that would limit compliance with study requirements

Patients with known allergy to mushrooms