Adding targeted covalent radiopharmaceutical (TCR) moiety to fibroblast activation protein inhibitor (FAPI) can increase tumor uptake and tumor retention in pre-clinical studies. This study is an open-labeled single-arm phase II diagnostic clinical trial to explore the clinical value of 68Ga-TCR-FAPI PET/CT in suspected malignant tumor patients.

TCR-FAPI can covalently bind to FAP that increase tumor uptake and tumor retention in pre-clinical studies, which elevates the ability for cancer imaging and facilitates the targeted radionuclide therapy. This study is an open-labeled single-arm phase II diagnostic clinical trial to explore the clinical value of 68Ga-TCR-FAPI PET/CT in suspected malignant tumor patients. Quantitative features (i.e., SUVmax) will be calculated to evaluate the PET images. Alternative imaging modality, including but not limited to, Ultrasound, CT, MRI, and PET/CT with other radiotracers, might be applied according to clinical needs. For patients who took surgery after multiple examination, tumor tissue and histopathology will also be obtained. For patients who underwent other treatment, treatment response of each individual lesion will be observed.

Inclusion Criteria:

• Suspected to have malignant tumors (supported by MRI and/or CT and/or tumor markers and/or pathology report), the tumor may be newly diagnosed or previously treated;
• Meet the indications for PET examination, show a clear indication and no contraindications;
• Have a performance status of score ≥ 80 on KPS scale or score 0-1 points on ECOG scale, a relatively good general situation;
• No major organ dysfunction (heart, lung, liver, kidney and other major organ include), acute or life-threatening status of infection;
• Be ≥ 18 years of age;
• Be willing and able to understand the research content and provide written informed consent/assent for the trial.

Exclusion Criteria:

• Have a history of imaging agent allergies;
• Does not meet the PET-CT scan sedation requirements, or has contraindications for PET-CT examination;
• Be pregnant or breastfeeding, or expecting to conceive or father children within the projected duration of the trial.