Biomarkers from circulating cell-free tumor DNA in peripheral blood will identify patients with metastatic prostate cancer diagnosed with C11 choline PET/CT who will benefit from metastasis-directed radiation, ablative therapies, and/or surgery. Tissue and blood will be collected before treatment. If patients receive androgen deprivation, then blood will be collected after neoadjuvant androgen deprivation but before radiation, ablative therapies, or surgery. Subsequent samples will be obtained at 3 months and 6 months following treatment, after which no further patient contact will occur.

Inclusion Criteria:

• Men age 18 years old and older.
• Histologically proven diagnosis of prostate cancer.
• Radiographic evidence of non-regional lymph node involvement, pelvic lymph node recurrence, and/or bone metastases.
• Requiring a clinically directed biopsy or resection of tumor at Mayo Clinic Rochester.
• Receiving local therapy for metastatic disease with radiation, ablative therapies, and/or surgery at Mayo Clinic Rochester.
• Willingness to provide blood sample prior to receipt of treatment, as well as after neoadjuvant androgen deprivation therapy and at 3 months and 6 months after radiation, ablation, or surgery.
• Absence of a second active malignancy.
• An understanding of the protocol and its requirements, risks, and discomforts.
• The ability and willingness to sign an informed consent.

Exclusion Criteria:

• Inability on the part of the patient to understand the informed consent or be compliant with the protocol.
• History of a serious or life-threatening allergic reaction to local anesthetics (i.e., lidocaine, xylocaine).

Men with metastatic prostate cancer