Inclusion Criteria:

- Patients with prostate cancer that is histologically confirmed by the Department of
Pathology at MSKCC will be considered if they show progression of disease based on
biochemical parameters. Patients with radiographic evidence of disease are not
eligible.

- Hormonal status will be recorded on the basis of serum testosterone levels.

- Patients who have progressed after primary therapy to include surgery or radiation
(with or without neo-adjuvant androgen ablation), or intermittent hormonal treatment
who have non-castrate levels of testosterone (>50 ng/ml). Patients with soft tissue
and/or bone disease or patients who are androgen- independent with no evidence of
radiographic disease are not eligible. Those patients who are symptomatic or who are
anticipated to develop symptoms within 6 months of entry will be excluded.

- Patients should have no change in their hormone therapies (with the exception of
therapies needed to maintain castrate levels of testosterone), including prednisone
or dexamethasone within two weeks prior to entry into study.

- Patients must have evaluable disease (by serial changes in PSA).

- Karnofsky performance status >60%.

- Patients must have adequate organ function as defined by:

- WBC > or = to 3500/mm3 platelet count > or = to 100,000 mm3.

- Bilirubin < or = 2.0 rag/100 ml or SGOT <3.0 X's the upper limit of normal.

- Creatinine < or = 2.0 mg/100 ml or creatinine clearance > or = 40 cc/min.

- Patients must have recovered from the toxicity of any prior therapy, and not received
chemotherapy or radiation therapy for at least 4 weeks prior to entry into the trial.

- No history of an active secondary malignancy within the prior five years except for
nonmelanoma skin cancer.

- Patients must be at least 18 years of age.

- Patients who have previously received suramin, may be treated if they have been off
this drug for at least 8 weeks and/or ha ve a documented plasma concentration below
50 mg/ml. For these patients, replacement doses of hydrocortisone are permitted.

- Patients must sign informed consent.

- Registration to IRB Protocol 90-40 (Correlative studies in human prostate cancer).

Exclusion Criteria:

- Clinically significant cardiac disease (New York Heart Association Class III/IV), or
severe debilitating pulmonary disease.

- Active CNS or epidural tumor.

- An infection requiring antibiotic treatment.

- Narcotic dependent pain.

- Anticipated survival of less than 6 months.

- Positive stool guaiac excluding hemorrhoids or history of documented radiation
induced proctitis.

- Allergy to seafood.

- Patients with radiographic evidence of metastatic disease.