Prospective Evaluation of 68Ga-FAPI PET in Biliary Cancers

Condition(s) studied

Investigational drug(s) / intervention(s)

gallium-68-Fibroblast Activation Protein Inhibitor: Gallium-68 Fibroblast Activation Protein Inhibitor (Ga-68 FAPI) is a radiolabeled molecular imaging tracer used for PET/CT imaging. It targets Fibroblast Activation Protein (FAP), which is highly expressed on cancer-associated fibroblasts within the tumor microenvironment in many epithelial malignancies, including biliary tract cancers. Ga-68 FAPI PET/CT provides high tumor uptake and improved tumor-to-background contrast, which may enhance detection of primary tumors, nodal disease, and distant metastases. It has demonstrated potential advantages over 18F-FDG PET/CT in sensitivity and diagnostic accuracy for staging and recurrence assessment.

Study summary

The goal of this prospective observational study is to evaluate whether Gallium-68 Fibroblast Activation Protein Inhibitor (FAPI) PET/CT can improve detection, staging, and recurrence assessment in adult patients (≥18 years) with suspected or confirmed biliary tract cancers, including gallbladder cancer, cholangiocarcinoma, and post-treatment suspected recurrence.

The main question(s) this study aims to answer are:

Can FAPI PET/CT provide greater sensitivity, specificity and diagnostic accuracy for primary tumors, nodal disease, and metastatic lesions compared to standard FDG PET/CT?

Does FAPI PET/CT offer additional diagnostic yield that may affect clinical decision-making and staging, potentially reducing need for invasive staging procedures?

Researchers will compare FAPI PET/CT with FDG PET/CT to see if FAPI improves detection of metastatic or recurrent disease, especially peritoneal or liver metastasis and lymph node involvement.

Participants will:

Provide written informed consent.

Undergo FAPI PET/CT imaging (baseline and/or at suspected biochemical or radiologic recurrence).

Have quantitative imaging parameters evaluated (SUVmax, tumor-to-liver ratios, metabolic volume).

May undergo comparison with FDG PET/CT and/or follow-up imaging or histopathology as gold standard.

Eligibility

Primary outcome measure(s)

• Diagnostic accuracy of Ga-68 FAPI PET/CT for detection of metastatic or recurrent disease (measured as sensitivity and specificity) — 1 Year

Trial sites (1)