18F-FDG versus 68Ga-FAPI-46 as PET tracer in ER-positive breast cancer - a pilot study

Phase 2

Recruiting

• Conditions: Hormone-positive breast cancer

• Registration Number: 2023-508066-15-01
• Lead Sponsor: University Hospital Maastricht

Brief Summary

The aim of this pilot study is to determine essential input parameters for an adequate sample size calculation for a diagnostic study that compares the diagnostic accuracy of 18F-FDG and 68Ga-FAPI-46 as PET-tracer in patients with ER+ breast cancer.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2024-03-11
• Study First Submitted QC: 2024-03-21
• Study First Posted: 2024-03-28
• Status Verified: 2025-09
• Study Start: 2025-09-01
• Last Update Submitted: 2025-09-19
• Last Update Posted: 2025-09-24
• Primary Completion: 2027-03
• Study Completion: 2027-03-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: Female
• Target Recruitment: 20

Inclusion Criteria

• Female patient with histopathologically proven ER+ breast cancer.
• Diagnosed with locally advanced (primary tumor >5 cm and/or presence of axillary lymph node metastases) or recurrent breast cancer, or metastatic breast cancer for which 18F-FDG PET/CT or 18F-FDG PET/MRI staging is performed.
• Willing and able to undergo the study procedures.
• Has personally provided written informed consent.

Exclusion Criteria

• Age <18
• Pregnancy
• Patients with secondary malignancies (except non-melanoma skin cancer)
• No 18F-FDG PET/CT or 18F-FDG PET/MRI scan.
• Contra-indications for PET/MRI such as pacemaker, aneurysm clips, metallic device in their body, severe claustrophobia, and severe obesity
• Chronic inflammatory disease such as rheumatoid arthritis.
• Patients with severe hepatic or renal impairment (eGFR ≤45mL/min/1.73m²)
• Inability to provide informed consent.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Primary Outcome Measures

Name	Time	Method
To determine essential input parameters for an adequate sample size calculation for a diagnostic study that compares the diagnostic accuracy of 18F-FDG and 68Ga-FAPI-46 as PET tracer in patients with ER+ breast cancer.	Patients will be followed from diagnosis until the additional imaging exams are performed, within 20 working days both PET exams will be performed.	To investigate the proportion of discordant pairs: the number of lesions detected on 18F-FDG PET but not on 68Ga-FAPI-46 PET and the number of lesions detected on 68Ga-FAPI-46 PET but not on 18F-FDG PET.

Secondary Outcome Measures

Name	Time	Method
To explore the feasibility of taking biopsies in test-positive patients.	Patients will be followed from diagnosis until the additional imaging exams are performed, within 20 working days both PET exams will be performed.	The proportion of 68Ga-FAPI-46-positive 18F-FDG-negative lesions for which performing a biopsy is not feasible.

Trial Locations

Locations (1)

Maastricht University Medical Center+; 🇳🇱 Maastricht, Netherlands