This is a clinical research study of an investigational (FDA IND-BB 10091) treatment of subjects with castration-resistant prostate cancer resistant to Taxanes (docetaxel, cabazitaxel) and evidence of disease progression on androgen-axis inhibition and/or immunotherapy in the form of sipuleucel-T.

The treatment is being evaluated for its effect on tumor growth. It consists of the placement (implantation) of small beads that contain mouse renal adenocarcinoma cells (RENCA macrobeads). The cells in the macrobeads produce substances that have been shown to slow or stop the growth of tumors in experimental animals and veterinary patients. It has been tested in 31 human subjects with different types of cancers in a Phase I safety trial. Phase II studies in patients with colorectal, pancreatic or prostate cancers are in progress.

Inclusion Criteria:

• Cancer of prostate
• Evidence of metastasis
• Failed available therapies
• Resolution of any toxic effects of previous therapies
• Performance status (ECOG PS) 0-2
• Adequate hematologic, coagulation (INR 2-3max), hepatic and renal function
• Life expectancy of 12 months
• Agrees to contraceptive use while on study if sexually active
• Sign informed consent document

Exclusion Criteria:

• Any condition presenting an unacceptably high anesthetic or surgical risk
• HIV positive
• Cognitive impairment such as to preclude informed consent
• Other surgical treatment, chemotherapy and radiation within four weeks of baseline
• Inadequate hematologic, coagulation (INR >3), hepatic, renal function
• Hepatic blood flow abnormalities and/or large-volume ascites
• Concurrent cancer of any other type except skin cancer (excluding melanoma)
• History of allergic reactions to mouse antigens
• Active infection, congestive heart failure, unstable angina, serious cardiac arrhythmias, psychiatric illness, difficult social situations not permitting reliable participation, active bleeding