[68]GA-FAPI-46 PET/CT for the Diagnosis of Metastatic Lesions in Patients With Lobular Breast Cancer (ICL). (FAPI-CL)

January 15, 2026 updated by: Hospices Civils de Lyon

[68]GA-FAPI-46 PET/CT for the Diagnosis of Metastatic Lesions in Patients With Lobular Breast Cancer (ICL)

Invasive squamous cell carcinoma (ISCC) represents 5 to 15% of breast cancers. Despite the rarity of this pathology, the number of patients with Invasive squamous cell carcinoma treated at HCL is significant.

Patients at risk of metastasis are usually referred to the HCL Nuclear Medicine departments to perform positron emission tomography - computed tomography (PET/CT) with [18]F-FDG as an extension assessment. The investigators know that [18]F-FDG PET/CT has limited diagnostic performance for assessing the extent of breast cancer with a sensitivity of 66-96% for all histologies combined. For the ISCC, these performances are even lower with average Standard Uptake Value (SUV) values of 3.4 [2.8-3.9] versus 6.6 [4.8-9.7] for the others histological types of breast cancer. False negatives in [18]F-FDG PET/CT are due to an insufficient osteoblastic and immune response in the tumor stroma. Avril & al. showed 65.2% false negatives with [18]F-FDG PET/CT for ISCC. This is why the search for new imaging techniques in this indication is particularly relevant.

Targeting fibroblast activation protein (FAP), a type II membrane glycoprotein belonging to the dipeptidyl peptidase-4 family, is a promising strategy for imaging tumor stroma, particularly in epithelial carcinomas .

The investigators would like to compare the [18]F-FDG PET/CT technique currently used to this new emerging modality.

The investigators hypothesize superior diagnostic performance of [68]Ga-FAPI PET/CT compared to [18]F-FDG PET/CT for the assessment of ISCC extension, with a gold standard histological.

The investigators translate this into the hypothesis of finding 30% of positive FAPI PET when the [18F]FDG PET/CT is negative or doubtful.

The advantage of this project and this new imaging modality is to not undertreat patients wrongly classified as non-metastatic. The investigators therefore wish to offer [68]Ga-FAPI PET/CT to patients with negative [18]F-FDG PET/CT.

The FAPICL project constitutes a seed project before a larger structuring study.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

45

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Adult patient (≥18 years old),
  • Beneficiary or entitled to a social security system;
  • Patient having agreed to participate in the study and signed written informed consent;
  • 18F-FDG PET/CT performed as part of the assessment of extension of an infiltrating lobular carcinoma, the result of which is negative or doubtful on at least one lesion.

Exclusion Criteria:

  • Pregnant, parturient or breastfeeding women. A pregnancy test before inclusion will be carried out for women of childbearing age.
  • Persons deprived of liberty by a judicial or administrative decision
  • People receiving psychiatric care
  • People admitted to a health or social establishment for purposes other than research
  • Adults subject to a legal protection measure (guardianship, curatorship)
  • Subjects participating in another interventional research including an exclusion period still ongoing at inclusion.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Control
Adult patients with infiltrating lobular carcinomas. Patients must have had a negative or doubtful 18F-FDG PET/CT scan as part of their routine care pathway
Other: [68]GA-FAPI-46 PET scan
Realization of a [68]GA-FAPI-46 PET scan to detect at least one [68]GA-FAPI positive lesion (confirmed by histology)

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Percentage of patients for whom at least one secondary lesion is demonstrated in [68]Ga-FAPI and confirmed by histology, when [18]F-FDG PET/CT is negative
Time Frame: 6 weeks
6 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Average number per patient of lesions demonstrated in [68]Ga-FAPI, not seen in [18F]-FDG
Time Frame: 6 weeks
This criteria will be collected when the imaging is read by a nuclear physician.
6 weeks
Number of lesions positive on histology, among the lesions visualized on PET/CT with [68]Ga-FAPI (and in the case of negative histology, identify the differential diagnoses)
Time Frame: 6 weeks
This criteria will be collected at the time of publication of the histological report of the suspicious lesion detected.
6 weeks
Evaluate the Positive Predictive Value of [68]Ga-FAPI PET/CT at the patient level, in patients negative on [18]F-FDG PET/CT
Time Frame: 6 weeks
This criterion will be collected at the time of publication of the histological report of the suspicious lesion detected.
6 weeks
Analyze the semi-quantitative values of the PET signal by describing the [68Ga]-FAPI lesional SUVs, compared to the vascular and hepatic background
Time Frame: 6 weeks
SUVmax bw lesion, SUVmax liver, SUVmax aorta will be collected at the time of reading the imaging by a nuclear physician, for each suspicious lesion
6 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Hospices Civils de Lyon

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

March 30, 2026

Primary Completion (Estimated)

May 30, 2027

Study Completion (Estimated)

August 30, 2027

Study Registration Dates

First Submitted

December 17, 2025

First Submitted That Met QC Criteria

December 17, 2025

First Posted (Estimated)

December 31, 2025

Study Record Updates

Last Update Posted (Estimated)

January 16, 2026

Last Update Submitted That Met QC Criteria

January 15, 2026

Last Verified

December 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 69HCL23_1133
  • 2025-524897-40-00 (Ctis)

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Breast Cancer

Clinical Trials on [68]GA-FAPI-46 PET scan

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Burundi

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe