This trial studies how well 68Ga-PSMA-11 PET scan works in imaging patients with prostate cancer. Diagnostic procedures, such as 68Ga-PSMA-11 PET may find and diagnose prostate cancer and improve monitoring of treatment response.

OUTLINE:

Patients receive gallium Ga 68-labeled PSMA-11 intravenously (IV) over 60-75 minutes then undergo PET/CT or PET/magnetic resonance (MR) scan over 2-4 minutes per bed position at baseline. Patients receiving systemic therapy undergo an additional 68Ga-PSMA-11 PET/CT or PET/MR scan 12 weeks after initiating therapy. Patients may also undergo CT and bone scan during screening and on study.

After the completion of study, patients are followed up at 60 days, 6 months, and annually up to 5 years or until time of first progression.

Inclusion Criteria:

• Pathologically proven prostate adenocarcinoma

• For the initial staging arm (initial staging cohort), high risk characteristics, including any of the following:

  • Grade group 4-5 and/or
  • PSA > 20 ng/mL

• For patients with biochemical recurrence (biochemical recurrence cohort):

  • Rising PSA after definitive therapy with prostatectomy or targeted local therapy (including but not limited to external beam radiation therapy, brachytherapy, high-frequency ultrasound, and cryotherapy)
  • If post-radical prostatectomy, PSA > 0.2 ng/mL measured > 6 weeks post-operatively and confirmatory persistent PSA greater than 0.2 ng/mL (American Urological Association (AUA) definition for biochemical recurrence
  • If post-radiation therapy, PSA that is equal to, or greater than, a 2 mg/mL rise above PSA nadir (American Society of Radiation Oncology (ASTRO) definition for biochemical recurrence)

• For patients undergoing systemic therapy (treatment monitoring cohort):

  • Diagnosis of metastatic castration-resistant prostate cancer
  • At least one or more measurable ( > 1 cm diameter in short axis) or evaluable lesions by any modality obtained within the past 60 days
  • Planned for treatment with standard of care androgen receptor pathway inhibitor or chemotherapy

• This can include patients who have already undergone a standard of care Ga-68 PSMA PET/CT or PET/MR for determining eligibility for Lu-177 PSMA therapy, for whom the PET/CT or PET/MR did not confirm eligibility for treatment with Lu-177 PSMA, and who are planned to start treatment on chemotherapy or androgen receptor signaling inhibitor (ARSI) within 30 days of the Ga-68 PSMA PET. This can also include patients who have obtained a standard of care Ga-68 PSMA PET/CT or PET/MR for rising PSA to help with restaging prior to starting new treatment with ARSI or chemotherapy, even if Lu-177 PSMA is not being considered at that time. Scan 1 must be completed within 30 days of enrollment. Any patient with an equivocal lesion by conventional imaging, regardless of where they are in the course of evaluation or treatment (equivocal lesion cohort)

• No other malignancy within the past 2 years (with the exception of skin basal cell or cutaneous superficial squamous cell carcinoma, superficial bladder cancer, carcinoma in situ in any location, or Rai Stage 0 chronic lymphocytic leukemia, which are allowed)

• Eastern Cooperative Oncology Group/World Health Organization (ECOG/WHO) performance status grades 0, 1, or 2

• Ability to understand and willingness to provide informed consent

Exclusion Criteria:

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