This study evaluates the diagnostic performance and safety of 18F-Thretide PET/CT in patients with biopsy proven prostate cancer who has no any form of therapy against prostate caner or suspected recurrence of prostate cancer who have negative or equivocal findings on conventional imaging.

Prostate-specific membrane antigen (PSMA) is overexpressed in most cases of prostate cancer and is potentially associated with metastasis and progression of prostate cancer. Compared with 68Ga, the PET radionuclide 18F exhibits several advantages. 18F-Thretide (18F-labeled PSMA ligand) has been studied for preclinical evaluation and Pilot Clinical Study. This study evaluates the diagnostic performance and safety of 18F-Thretide PET/CT in patients with with biopsy proven prostate cancer who has no any form of therapy against prostate caner or suspected recurrence of prostate cancer who have negative or equivocal findings on conventional imaging.

Inclusion Criteria:

• Male ≥ 18 years of age;
• For patients with newly diagnosed prostate cancer : (1) adult patients with PCa confirmed by biopsy; (2) no any form of therapy against PCa within last three months; (3) planned surgical treatment;
• For patients with suspected recurrence of prostate cancer: (1)Histopathologically confirmed prostate adenocarcinoma per original diagnosis, with subsequent definitive therapy; (2)Suspected recurrence of prostate cancer based on rising PSA after definitive therapy on the basis of: Post-radical prostatectomy: Detectable or rising PSA level ≥ 0.2 ng/mL with a confirmatory PSA ≥ 0.2 ng/mL ; or Post-radiation therapy, cryotherapy, or brachytherapy: Increase in PSA level that is elevated by ≥ 2 ng/mL above the nadir;
• Life expectancy ≥3 months as determined by the investigator;
• Able and willing to provide informed consent and comply with protocol requirements.

Exclusion Criteria:

• Known allergic history to fluoride 18F-Thretide injection and/or 99mTc-MDP or its excipients;
• Patients who cannot tolerate intravenous administration (such as a history of needle sickness or blood sickness);
• Those who are not suitable for or unable to complete PET or other imaging examinations due to special reasons, including claustrophobia and radiophobia, etc.
• Practitioners requiring prolonged exposure to radioactive conditions;
• Serious diseases of the heart, kidney, lung, vascular, nervous and psychiatric systems, immune deficiency diseases and hepatitis/cirrhosis;
• Have been diagnosed with clinical recurrence of prostate cancer;
• Patients receiving ADT treatment or chemotherapy;
• Patients who participated in clinical trials of radiopharmaceuticals within the previous 1 year;
• Participated in other interventional clinical trials within 1 month prior to screening;
• There are other conditions that the researcher considers inappropriate to participate in this study.