Ga-68 PSMA Ligand: A Radiopharmaceutical for Localization of Prostate Cancer
Condition: Latent Cancer Prostate
MeSH terms: Prostatic Neoplasms
Study type: Interventional
Phase: Phase 2

Summary: 
      This is an open-label single arm clinical trial, plan to enroll approximately a total of 62
      evaluable subjects. According to the estimated missing rate 15%, the sample size in this
      study is 73.

      Inclusion criteria:

      To be eligible for inclusion, each patient must fulfill all of the following criteria:

        1. Age equals or more than 20 years old

        2. Willing to sign the informed consent

        3. Pathology-proved intermediate to high risk group prostate cancer patients (PSA > 10
           ng/mL, or Gleason score 7-10, or clinical stage >T2a) OR Prior radiotherapy or
           prostatectomy for prostate cancer with biochemical recurrence defined as:

             -  post prostatectomy: increase in PSA of > 0.2 ng/mL in two or more consecutive blood
                samples

             -  post radiotherapy: PSA levels of ≥ 2 ng/mL above the post-therapy nadir

        4. Life expectancy more than 3 months

      Exclusion criteria:

      Patient who has any of the following criteria will be excluded from the trial:

        1. Unable to tolerate the PET/CT scan, such as those with claustrophobia, unable to lie
           still, consciousness unclear, vital sign unstable.

        2. With renal impairment (glomerular filtration rate lower than 30 ml/min/1.73 m2), and
           allergy to medium contrast

        3. Unable to give informed consent.

        4. Allergy history to Ga68-PSMA ligand, significant abnormal lab data (ALT more than three
           times of normal value), and high risk to conduct examination after evaluations of PI.

        5. Patient had malignancy history
    

Detailed description: 
      It is a phase II single-arm clinical trial. The primary endpoint is diagnostic sensitivity of
      the Ga-68 PSMA ligand in prostate cancer. The four outcomes (true positive, false positive,
      true negative, and false negative) can be defined based on the process as Figure 1 and
      formulated in a 2×2 contingency table, and the related sensitivity, specificity, and accuracy
      will be calculated based on the test results of enrolled subjects. All subjects enrolled must
      meet eligibility criteria based on the inclusion/exclusion criteria detailed in Section 5.4
      and 5.5.

      Time elapsed from the last PSA determination until PET was no more than 2 weeks in all
      patients. Patients will receive complementary workups including MRI (for patients suspicious
      for local or regional node recurrence), bone scan (for patients suspicious for distant bone
      metastasis), contrast CT (for patients suspicious for visceral organ metastasis or lung
      metastasis) subsequently after Ga68-PSMA ligand PET/CT scan no longer than two weeks.

      All of the images were interpreted by a team of two nuclear medicine physicians and one
      radiologist. In cases of questionable findings, the decision was made by consensus of at
      least two observers using pre-specified criteria. All of the readers were blinded to the
      patient's clinical history, blood tests, and previous imaging findings. If patient have
      consistent findings between Ga68 PSMA ligand PET/CT and other complementary workups, the
      patients are deemed as true positive or negative. For patients with discrepancy image
      findings between Ga68 PSMA ligand PET/CT and the other complementary workups, biopsy, needle
      aspiration or operation will be arranged for histology confirmation. The final results of
      Ga68-PSMA ligand PET/CT scan will be depend on the consensus of multidisciplinary tumor board
      based on all integrated informations.
    

Intervention name(s): Ga-68 PSMA ligand
Intervention type(s): Drug
Intervention description(s): For PET/CT PSMA ligand scan, the subject will have catheter(s) placed for intravenous administration of [68Ga]PSMA ligand . Subjects will receive a single intravenous bolus of 2-5 mCi [68Ga]PSMA ligand and received PET/CT scan 60 minutes later. The data acquisition begin with non-contrast CT at 120kVp, automated mAs, and a pitch of 1.5, followed by PET acquisition from the mid-thigh to skull-base, 3 minutes each bed. After image acquisition, the subject will be observed for half an hour, and will be discharged if no adverse event happens.
The estimated organ doses show that the kidneys and the urinary bladder wall were the organs with the highest dose. As presented, the effective doses for patients were 0.023 mSv/MBq ± 15% (maximum deviation), leading to an effective dose of 3.4 mSv for an injected activity of 150 MBq.
Other intervention name(s): Ga-68 PSMA-11, PSMA-HBED-CC
Intervention MeSH terms: Gallium 68 PSMA-11
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: cancer prostate; Ga-68 PSMA Ligand; staging; biochemical failure