CTC Immune Checkpoint

Patients will be eligible for inclusion in this study only if all of the following criteria apply:

• Histologically confirmed diagnosis of adenocarcinoma of the prostate. Small cell or neuroendocrine tumors of the prostate are also permitted.
• Clinical or radiographic evidence of progressive metastatic disease, with progression defined as a rising PSA, new metastatic lesions (bone or soft tissue), or radiographic evidence of tumor growth on CT or MRI.
• Age ≥ 18 years.
• Ability to understand and the willingness to sign a written informed consent document.

In addition to meeting all of the above criteria, patients must meet all of the criteria for one of the following groups:

A) mCRPC starting sipuleucel-T (Provenge) with or without abiraterone acetate or enzalutamide

• For patients with adenocarcinoma of the prostate (not applicable for patients with small cell or neuroendocrine tumors of the prostate, or those receiving ADT therapy): Castrate levels of testosterone (≤ 50 ng/dl)
• Patient planning to start sipuleucel-T.
• Enrollment prior to the initiation of sipuleucel-T.

B) mCRPC with visceral or high risk disease pre-abiraterone/enzalutamide

• For patients with adenocarcinoma of the prostate (not applicable for patients with small cell or neuroendocrine tumors of the prostate, or those receiving ADT therapy): Castrate levels of testosterone (≤ 50 ng/dl)
• Visceral OR high risk disease - must meet one of the following categories:

• Visceral disease: Radiographic evidence of liver, adrenal, pulmonary, or brain metastases
• High risk disease: Presence of at least 2 of the following factors:

• Bone pain requiring opioids
• Anemia (Hgb <13 g/dL)
• Bone scan progression at baseline
• >2 sites of metastatic disease
• Karnofsky Performance Status (KPS) ≤ 70
• PSA doubling time <3 months
• Patient planning to start abiraterone acetate or enzalutamide.
• Enrollment prior to the initiation of abiraterone acetate or enzalutamide.

C) Newly diagnosed metastatic castration sensitive prostate cancer (mCSPC) starting androgen deprivation therapy

• Evidence of metastatic disease on radiographic imaging
• Enrollment within 2 weeks of initiation of androgen deprivation therapy (ADT).
• Lack of history of hypogonadism

D) Enzalutamide or abiraterone acetate resistant mCRPC

• For patients with adenocarcinoma of the prostate (not applicable for patients with small cell or neuroendocrine tumors of the prostate, or those receiving ADT therapy): Castrate levels of testosterone (≤ 50 ng/dl)
• Evidence of disease progression on or following enzalutamide or abiraterone acetate, as defined by one of the following:

• Radiographic evidence of disease progression as defined by new bone scan lesions or growth of existing soft tissue/visceral/lymph node/bone metastases as determined by the investigator
• Clinical progression of disease with cutaneous lesions or palpable lesions in absence of radiographic progression

Exclusion criteria

• History of intercurrent or past medical or psychiatric illness that would make participation in a blood drawing protocol difficult or not feasible at the discretion of the principal investigator or co-investigator(s).
• Treatment with an anthracycline (including mitoxantrone) within 1 week of CTC collection, as anthracyclines cause auto-fluorescence of cells.