An observational study in Cancer of Unknown Primary Site, sponsored by First Affiliated Hospital of Zhejiang University. Not yet recruiting at 1 site in China. Open to participants aged 20 Years to 85 Years. Per ClinicalTrials.gov, last updated 2026-01-28.
Sponsored by First Affiliated Hospital of Zhejiang University · Observational
This study aims to evaluate the diagnostic efficacy, therapeutic assessment, prognostic analysis, and impact on clinical treatment decisions of 18F-FAPI PET/CT in patients with cancer of unknown primary.
Primary endpoint: Diagnostic efficacy of 18F-FAPI PET/CT in patients with undetermined primary tumor (sensitivity, specificity, accuracy).
secondary end points:
The diagnostic performance of 18F-FAPI PET/CT compared with CT, MR and 18F-FDG PET in the clinical application of cancer with unknown primary site was compared.
④Assess the heterogeneity of sensitivity and specificity of 18F-FAPI PET/CT for different system sites (neck/thorax/abdomen).
101 studies on the registry are indexed under Neoplasms, Unknown Primary; 19 are open to participants now.
This study's planned enrollment of 120 is close to the median of 125 across 25 observational studies indexed under Neoplasms, Unknown Primary.
Browse Neoplasms, Unknown Primary studies →First Affiliated Hospital of Zhejiang University is the lead sponsor of 263 studies on the registry; 144 are open to participants now.
Counted across the registry records on this site, refreshed daily.
120
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
FAPI PET scan in patients with CUPs
Diagnostic Test: 18F-FAPI PET
18F-FAPI-04 PET/CT
Diagnostic efficacy
Sensitivity, specificity, positive and negative predictive value of 18F-FAPI PET/CT Imaging in cancers of unknown primary site
Time frame: through study completion, an average of 1.5 year
Standard uptake value （SUV）of tumor
This measure evaluates the association between baseline 18F-FAPI PET parameters (e.g., SUVmax, SUVmean).
Time frame: through study completion, 3-4 years
Metabolic tumor volume (c) and total lesion glycolysis (TLG) of tumor
This measure evaluates the association between baseline 18F-FAPI PET parameters (MTV in cm3, TLG in cm3\*SUV）
Time frame: through study completion, 3-4 years
Prognostic Value of Baseline 18F-FAPI PET for Progression-Free Survival (PFS) in High-Risk Patients
Prognostic Value of Baseline 18F-FAPI PET for Progression-Free Survival (PFS) in High-Risk Patients
Time frame: through study completion, 3-4 years
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Undecided
This study is not yet recruiting, as verified in Dec 2025. You cannot join it, but the record below documents what was studied.
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First Affiliated Hospital of Zhejiang University →