Initial Staging of Lobular Breast Carcinoma: Head to Head Comparison of 68Ga-FAPI-46 and 18F-FDG PET/CT (GALILEE)

Lobular Breast cancer staging with 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) is not optimal due to the poor accumulation of 18F-FDG in the tumour. Through better sensitivity (and specificity), 68Ga-FAPI-46-46 PET should provide a more accurate staging of lobular breast cancer than 18F-FDG PET.

Study Overview

• Status: Active, not recruiting
• Conditions: Lobular Breast Carcinoma
• Intervention / Treatment: Diagnostic test: 68Ga-FAPI-46 PET scan

Detailed Description

Research hypothesis : Through better sensitivity (and specificity), 68Ga-FAPI-46-46 PET should provide a more accurate staging of lobular breast cancer than 18F-FDG PET. Participants with lobular breast carcinoma will then undergo 18F-FDG and 68Ga-FAPI-46 PET scan.

Primary objective of the study is to compare the sensitivity of 68Ga-FAPI-46 with the sensitivity of 18F-FDG in the detection of lobular breast carcinoma lesions, measured by positron emission tomography (PET). These results will be compared with the histological data collected before or during surgery (conventional histological data and immunohistochemical labeling of FAPα on the sample obtained), clinical follow-up and any results of additional examinations carried out within the usual clinical follow-up of the patients.

Comparison of primary tumor and metastases uptake of 68Ga-FAPI-46 with the uptake of 18F-FDG, radiomic study of 68Ga-FAPI-46 PET and comparative radiomic study of 68Ga-FAPI-46 PET and 18F-FDG PET and comparison of the specificity of 68Ga-FAPI-46 with the specificity of 18F-FDG after a 12-month follow-up will also be performed as secondary objectives.

• Study Type: Interventional
• Enrollment (Actual): 40
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Monaco
  • Monaco, Monaco, 98000
    • Centre Hospitalier Princesse Grace

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age greater than or equal to 18 years
• ECOG from 0 to 2
• Histological diagnosis of Lobular Carcinoma of the breast based on a breast biopsy
• Patient naïve to any treatment for lobular breast carcinoma
• Women of childbearing age should have an adequate method of contraception
• Patient having voluntarily accepted to participate in the study and signed the informed consent
• Minimum tumor stage IIA
• Sufficient histological material in the biopsy or the surgical specimen, if the biopsy is insufficient

Exclusion Criteria:

• PET scan contraindications: severe claustrophobia, unbalanced diabetes during 18F-FDG PET scans (fasting capillary blood sugar ≥ 11 mmol)
• Hormone therapy started
• 18F-FDG PET scan > 21 days
• Pregnant women, parturients and nursing mothers
• Persons deprived of liberty by a judicial or administrative decision
• Persons admitted to a health or social establishment for purposes other than research
• Adults who are the subject of a legal protection measure or who are unable to express their consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 68Ga-FAPI-46 PET scan + 18-FDG PET scan	Diagnostic test: 68Ga-FAPI-46 PET scan; 68Ga-FAPI-46 is a radiotracer for the detection of Fibroblast Activation Protein (FAP) in cancer patients. 68Ga-FAPI-46 will be administered intravenously at a dose of 2MBq/kg. Patients will be scanned 60 minutes after administration of 68Ga-FAPI-46.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of positive tumor lesions, i.e. confirmed by additional imaging, histopathology/biopsy or response to treatment (on imaging or clinical assessment)	Number of positive tumor lesions of 68Ga-FAPI-46 PET scan in comparison with 18F-FDG PET scan	Up to 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
SUVmaxFAPI and SUVmaxFDG for each target (Standardized Uptake Value)	Comparison of 68Ga-FAPI-46 and 18F-FDG Standardized Uptake Value in the primary tumor and possible metastases	Up to 21 days
SUVmaxFAPI/reference and SUVmaxFDG/reference activity ratios	Comparison of (SUVmaxFAPI/reference) and (SUVmaxFDG/reference) activity ratios. For the primary tumour, the reference activity will be measured in either the periphery of the lesion or on a homologous healthy tissue. For a vertebral metastasis, the reference activity will be measured in an adjacent healthy vertebra.	Up to 21 days
MTVFAPI and MTVFDG (Metabolic Tumor Volume)	Comparison of MTVFAPI and MTVFDG in the primary tumor and possible metastases	Up to 21 days
Number of discrepancies between FAPI and FDG PET scans	Discrepancies (discordant pairs) between 68Ga-FAPI-46 PET scan and 18F-FDG PET scan will be analyzed	Up to 21 days
Correlation between PET scan and FAPα labeling	Correlation between PET scan results and measurement of the FAPα labeling density on the biopsy	Up to 12 months
Correlation between PET scan and breast histology	Correlation between PET scans results and standard measurements in breast histology: OR (estrogen receptors), PR (progesterone receptors), HER2 (Human Epidermal Growth Factor Receptor-2), Ki-67 antigen, Ecadherin	Up to 12 months
Specificity comparison	Specificity of 68Ga-FAPI-46 PET scan will be compared to 18F-FDG PET scan specificity	12 months
Correlation between tumor lesion radiomics and histological characteristics	1st order characteristics reflecting the distribution of gray levels determined by radiomics study of 68Ga-FAPI PET scan and 18F-FDG PET scan	12 months
Molecular biology analysis of tumor samples	Bioinformatics analysis of tumor sample celullar composition in terms of fibroblasts expressing FAP protein after total RNA extraction.	12 months

Collaborators and Investigators

• Sponsor: Centre Hospitalier Intercommunal de Toulon La Seyne sur Mer
• Collaborators: Centre Antoine Lacassagne; Institut Curie
• Investigators: Study Director: Florent Hugonnet, MD, Centre Hospitalier Princesse Grace

Study record dates

Study Major Dates

• Study Start (Actual): November 16, 2023
• Primary Completion (Estimated): November 1, 2026
• Study Completion (Estimated): November 1, 2026

Study Registration Dates

• First Submitted: June 16, 2023
• First Submitted That Met QC Criteria: June 27, 2023
• First Posted (Actual): July 5, 2023

Study Record Updates

• Last Update Posted (Actual): April 13, 2026
• Last Update Submitted That Met QC Criteria: April 10, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: staging; 18F-FDG PET; 68Ga-FAPI-46; FAPα
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Neoplasms by Histologic Type; Neoplasms, Glandular and Epithelial; Adenocarcinoma; Skin Diseases; Breast Diseases; Carcinoma; Neoplasms, Ductal, Lobular, and Medullary; Breast Neoplasms; Skin and Connective Tissue Diseases; Carcinoma, Lobular; Molecular Mechanisms of Pharmacological Action; Radiopharmaceuticals; FAPI-46
• Other Study ID Numbers: 2023-CHITS-006

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No