Ga-68 PSMA Ligand: A Radiopharmaceutical for Localization of Prostate Cancer

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.