Characterizing Breast Cancer With 68Ga-FAPI PET/CT (PFB-01)

Study Overview
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Brief Summary
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Fibroblast activation protein (FAP) is overexpressed in cancer-associated fibroblasts (CAFs), which constitute a major proportion of cells within the tumor microenvironment, especially in breast cancer. 68Ga-FAPI has been developed as a tumor-targeting agent. This prospective study is going to investigate the performance and value of 68Ga-FAPI PET/CT in patients with breast cancer.

Detailed Description
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Breast cancer is a complex, heterogeneous disease comprising numerous distinct biological subtypes characterized by variant pathobiological features and clinical behaviors. 18F-fluorodeoxyglucose (18F-FDG) PET/CT, an essential imaging modality in the characterization of metabolism within the tumor, has successfully evolved in the diagnosis, staging, and assessment of treatment response in patients with breast cancer. Cancer-associated fibroblasts (CAFs) are a crucial component of the tumor stroma with diverse functions. Fibroblast activation protein (FAP), a type II membrane-bound glycoprotein from the dipeptidyl peptidase-4 family, is highly expressed in the CAFs of several epithelial carcinomas, including breast cancer, coupled with relatively low expression in normal tissue. Gallium-68 (68Ga)-conjugated FAP inhibitor (FAPI), a new radiotracer targeting FAP, has been developed for targeting FAP and tumor-stromal visualization. With its fast renal clearance and high tumor-to-background ratio, 68Ga-FAPI has been successfully validated in multi-types of tumors. This study aims to evaluate the performance and value of 68Ga- FAPI PET/CT in patients with breast cancer.

Official Title
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Accuracy and Safety of 68Ga-FAPI PET/CT in the Diagnosis of Axillary Lymph Node Metastasis in Early Breast Cancer Patients: A Prospective Cohort Study

Conditions
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Breast Cancer

Intervention / Treatment
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* Diagnostic Test: 68Ga-FAPI PET/CT scan


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age 18-80 years old; newly diagnosed BC confirmed by biopsy or with BI-RADS category 4C or 5 lesions by US or MG; BC clinical stagecT1-3 cN0-3 M0; no prior treatment for BC. Exclusion Criteria: pregnancy; breastfeeding; patients who were unwilling to undergo PET/CT scans.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 68Ga-FAPI PET/CT<br>Inject 68Ga-FAPI and then perform PET/CT scan. | Diagnostic Test: 68Ga-FAPI PET/CT scan<br>* Patients with suspected breast cancer underwent 68Ga-FAPI PET/CT after an injection of 74-148 MBq (2-4 mCi) 68Ga-FAPI to image lesions of breast cancer.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnostic Performance (1) | Diagnostic performance including sensitivity, specificity, accuracy, positive predictive value and negative predictive value of 68Ga-FAPI PET/CT in the detection of ALN metastasis according to the pathological reference standard on a per-patient basis, compared with 18F-FDG PET/CT and ultrasound. | Through study completion, an average of 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical Stage | Clinical stage changed by 68Ga-FAPI PET/CT compared to 18F-FDG PET/CT. | Through study completion, an average of 1 year | 
| Diagnostic Performance (2) | Diagnostic performance of ALN metastasis of 68Ga-FAPI PET/CT with or without previous biopsy on breast lesion. | Through study completion, an average of 1 year | 
| Safety | Short-term adverse effects (AEs) after 68Ga-FAPI injection. | Through study completion, an average of 1 year |