Ga68-FAPI-46 PET/CT for Preoperative Assessment of Peritoneal Carcinomatosis

Not Applicable

Recruiting

• Conditions: Peritoneal Carcinomatosis; Cancer
• Interventions: Diagnostic Test: FAPI PET/CT

• Registration Number: NCT06061874
• Lead Sponsor: Jules Bordet Institute

Brief Summary

This is a prospective, phase II, non-randomized clinical imaging trial. Ga68-FAPI-46 is a novel radiotracer used in PET/CT imaging, targeting a protein of the tumor microenvironment called FAP (Fibroblast activation protein).

The aim of the study is to assess the accuracy of Ga68-FAPI-46 PET/CT for preoperative assessment of peritoneal carcinomatosis in colorectal and ovarian cancer.

Detailed Description

Fibroblast activation protein (FAP) is a type II transmembrane glycoprotein expressed on the surface of cancer-associated fibroblasts (CAFs) in the stroma of various tumor entities. Recently, radiolabeled molecules targeting the FAP, called FAP inhibitors (FAPI) labelled with Gallium-68, have been developed for molecular imaging with PET/CT (positron emission tomography/computed tomography). This radiotracer often presents a higher cancer lesion detectability than F18-FDG (fluorodeoxyglucose), partly thanks to its higher tumour-to-background ratio achieved by a low background activity, particularly in the brain, abdominal cavity and liver. These advantages have resulted in a superior sensitivity of Ga68-FAPI PET/CT over F18-FDG and higher SUV (standardized uptake value) in evaluating various types of cancer. In this context, Ga68-FAPI PET/CT seems promising to further study as a clinical imaging modality for preoperative assessment of peritoneal carcinomatosis.

In this study, the investigators correlate Ga68-FAPI PET/CT findings in terms of peritoneal involvement with intraoperative findings based on histopathology and try to find out how accurate Ga68-FAPI PET/CT is for the preoperative assessment of peritoneal carcinomatosis.

Study Timeline

• Study Start: 2023-05-30
• Study First Submitted: 2023-08-31
• Study First Submitted QC: 2023-09-25
• Study First Posted: 2023-09-29
• Status Verified: 2025-03
• Last Update Submitted: 2025-03-26
• Last Update Posted: 2025-03-31
• Primary Completion: 2025-06
• Study Completion: 2025-12

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 80

Inclusion Criteria

• Histologically proven colorectal and ovarian cancer.
• Known or suspected peritoneal metastases from the tumour of origin.
• Scheduled for peritoneal complete cytoreductive surgery with curative intent with or without neoadjuvant chemotherapy.
• ECOG (Eastern Cooperative Oncology Group) Performance status ≤2.
• Signed written informed consent obtained before any study-specific screening procedures.

Exclusion Criteria

• Non-resectable extra-abdominal metastasis and/or >3 hepatic metastases on standard work-up
• Known chronic inflammatory conditions including the intestinal system (eg. inflammatory bowel disease, Crohn's disease)
• Pregnant and lactating women
• Previous or concurrent malignancy diagnosed within the last 3 years except adequately treated in situ carcinoma of the cervix uteri and basal or squamous cell skin cancer.
• Subjects with another significant medical condition which, in the investigator's opinion, may interfere with the completion of the study.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
FAPI PET/CT	FAPI PET/CT	Patients with known or suspected peritoneal metastases from colorectal and ovarian cancers scheduled for complete cytoreductive surgery undergo FAPI PET/CT before the planned surgery. In the target population, patients receiving neoadjuvant chemotherapy undergo FAPI PET/CT both before and after chemotherapy.

Primary Outcome Measures

Name	Time	Method
Correlation of the Ga68-FAPI PET/CT derived PCI (peritoneal cancer index) score with the intraoperative PCI based on histopathology of resected specimen (the reference standard)	Through completion of post-surgical pathological examination, up to 2 years since the study initiation	Intraoperative PCI validated by histopathology performed on resected peritoneal metastases obtained during peritoneal cytoreductive surgery/explorative laparoscopy or laparotomy will be correlated with Ga68-FAPI PET/CT derived PCI.

Secondary Outcome Measures

Name	Time	Method
Assessment of the impact of neoadjuvant chemotherapy on the FAPI expression of target lesions at baseline.	Through completion of post-neoadjuvant chemotherapy FAPI PET examination,up to 2 years since the study initiation	Subgroup: Patients receiving neoadjuvant chemotherapy Treatment-induced change in the total peritoneal tumor volume and uptake intensity of FAPI on PET/CT will be assessed and correlated to histopathological findings.
Comparison of PCI obtained with Ga68-FAPI PET/CT to the PCI calculated on standard preoperative imaging.	Through completion of imaging examinations, up to 2 years since the study initiation	PCI calculated on standard preoperative imaging (MRI and FDG PET/CT) will be correlated with Ga68-FAPI PET/CT derived PCI.

Trial Locations

Locations (1)

Institut Jules Bordet; 🇧🇪 Brussels, Belgium