18F-FDG Versus 68Ga-FAPI-46 as PET Tracer in ER-positive Breast Cancer.

Maastricht University Medical Centre (MUMC)

Status and phase

Enrolling

Phase 2

Conditions

Breast Cancer

Breast Diseases

Breast Neoplasms

Treatments

Diagnostic Test: 68Ga-FAPI-46 PET/CT and 68Ga-FAPI-46 PET/MRI

Study type

Interventional

Funder types

Other

Identifiers

NCT06335069

2023-508066-15

Details and patient eligibility

About

The extent of breast cancer is an important prognostic factor in patients diagnosed with this disease. Therefore, adequate staging at diagnosis is a requisite for optimal treatment. In all patients diagnosed with locally advanced breast cancer (LABC), distant staging using 18F-FDG PET/CT is recommended. However, the degree of metabolic uptake in the primary breast tumor is significantly lower in the ER+ subtype compared to HER2+ and triple negative breast cancer (TNBC). As a consequence, a suboptimal 18F-FDG uptake in ER+ breast cancer patients can potentially lead to missed distant metastases. Fibroblast-activating protein inhibitor (FAPI) is a recently developed radiotracer that binds to FAP, a stromal antigen overexpressed in more than 90% of epithelial-derived tumors and their metastases. Previous studies all show 68Ga-FAPI PET/CT to have a higher detection rate compared to 18F-FDG PET/CT. However, all previous studies were performed without considering breast cancer subtype. If the metabolic uptake by 68Ga-FAPI-46 is higher in ER+ breast cancer patients, more lesions will be detected, resulting in a more appropriate treatment for these patients. Therefore, in this pilot study, the investigators aim to compare the diagnostic performance of 18F-FDG with 68Ga-FAPI-46 as PET-tracer in ER+ breast cancer patients.

Enrollment

20 estimated patients

Sex

Female

Ages

18+ years old

Volunteers

No Healthy Volunteers

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.