The objective of the study is to construct a noninvasive approach 68Ga-XACP3 PET/CT to detect tumor lesions in patients with prostate cancer and to compare with 68Ga-PSMA PET/CT.

As a new ACP3 targeting PET radiotracer, 68Ga-XACP3 is promising as an excellent imaging agent applicable to prostate cancer. In this research, subjects with prostate cancer or highly suspected recurrence detection underwent contemporaneous 68Ga-XACP3 and standard-of-care imaging (68Ga-PSMA PET/CT) either for an initial assessment or for metastases or highly suspected recurrence detection. Tumor uptake was quantified by the maximum standard uptake value (SUVmax). The numbers of positive tumor lesions of standard-of-care imaging and 68Ga-PSMA PET/CT were recorded by visual interpretation. The diagnostic accuracy of 68Ga-XACP3 was calculated and compared to standard-of-care imaging.

Inclusion Criteria:

• Adult patients (aged 18 years or older);
• Patients with newly diagnosed, highly suspected recurrence or previously treated metastases of prostate cancer (supporting evidence may include MRI, CT, tumor markers, and pathology report);
• Patients who had scheduled both standard-of-care imaging (68Ga-PSMA PET/CT) and 68Ga-XACP3 PET/CT scans;
• Patients who were able to provide informed consent (signed by participant, parent or legal representative) and assent according to the guidelines of the Clinical Research Ethics Committee.

Exclusion Criteria:

• The inability or unwillingness of the research participant or legal representative to provide written informed consent.