[18F]F-FAPI PET/CT and Laparoscopy in Staging Advanced Gastric Cancer

Phase 2

Recruiting

• Conditions: Locally Advanced Gastric Adenocarcinoma; PET-CT; STOMACH NEOPLASM; Gastric Cancer
• Interventions: Diagnostic Test: [18F]FAPI-74 PET/CT; Drug: [18F]-FAPI-74

• Registration Number: NCT07018661
• Lead Sponsor: Leiden University Medical Center

Brief Summary

The goal of this clinical trial is to learn if a new type of scan, FAPI-PET/CT, can help find metastases of gastric cancer. We want to know how well this scan works for this purpose and whether it is less burdensome for patients compared to the methods we currently use to find metastases.

The main questions it aims to answer are:

* In how many patients can FAPI-PET/CT find metastases, which leads to a change in their treatment plan as decided by their medical team, such as avoiding unnecessary surgeries and changing from treatment meant to cure the disease to treatment focused on comfort (palliative treatment)?

* In how many patients does FAPI-PET/CT change the diagnostic process as decided by their medical team, like more biopsies or imaging, or changing the type (extent) of surgery needed?

Apart from the usual care gastric cancer patients receive, participants will:

* Undergo one additional scan, which will take approximately 2 hours in total (excluding travel time)

* Complete a number of questionnaires, which will take approximately 4 hours in total

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2025-04-04
• Study First Submitted QC: 2025-06-10
• Study First Posted: 2025-06-12
• Study Start: 2025-07-03
• Status Verified: 2025-08
• Last Update Submitted: 2025-08-20
• Last Update Posted: 2025-08-27
• Primary Completion: 2028-01
• Study Completion: 2029-01-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 250

Inclusion Criteria

• Histologically proven adenocarcinoma of the stomach or the esophagogastric junction (Siewert type III), by gastroscopy;
• Age greater than or equal to 18 years;
• Surgically resectable, advanced tumor (cT3-4b, N0-3, M0), as determined on gastroscopy and a contrast-enhanced CT of thorax and abdomen. Intention to perform a gastrectomy, based on a multidisciplinary team meeting and shared decision making;
• Patients must have given written informed consent;
• Patients who have recently participated in an interventional study with an investigational medicinal product (IMP) may only participate if an interaction with study procedures is deemed unlikely by the study team (e.g. based on mechanism or washout period).

Exclusion Criteria

• Siewert type I-II esophagogastric junction tumor;
• Unfit or unwilling to undergo study procedures;
• Unfit or unwilling to undergo surgery;
• Pregnancy at time of the [18F]AlF-FAPI-74 PET/CT scan, due to the investigational PET radiation burden;
• Incapacitated subjects without decision-making capacity;
• Medical or psychiatric conditions that compromise the patient's ability to give informed consent;
• Illiterate patients unable to complete the resource use and quality of life questionnaires;
• Inability to undergo PET/CT scans due to factors such as claustrophobia, weight limits, or the inability to lie flat for the duration of the scan (approximately 30 minutes).

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
[18F]-FAPI-74 PET/CT	[18F]FAPI-74 PET/CT	3.0 MBq \[18F\]-FAPI-74 will be administered intravenously 60 minutes before PET/CT scanning. Scanning time will be dependent on the type of scanner in the participating center, but will take approximately 20 minutes.
[18F]-FAPI-74 PET/CT	[18F]-FAPI-74	3.0 MBq \[18F\]-FAPI-74 will be administered intravenously 60 minutes before PET/CT scanning. Scanning time will be dependent on the type of scanner in the participating center, but will take approximately 20 minutes.

Primary Outcome Measures

Name	Time	Method
Change in treatment intent	For each patient from enrollment through study completion, an average of 1 year.	Proportion of patients in whom \[18F\]AlF-FAPI-74 PET/CT leads to detection of M1-disease resulting in change in treatment intent determined by the local multidisciplinary team (MDT) meetings, including: * The number of prevented unnecessary surgeries (staging laparoscopies and/or gastrectomies); * The number of changes from curative to palliative treatment
Change in diagnostic work-up	Immediately after completion of clinical staging. Clinical staging consists of FAPI-PET/CT, additional diagnostics following FAPI-PET/CT (if necessary to confirm suspect lesions on FAPI-PET/CT) and/or diagnostic laparoscopy	Proportion of patients in whom \[18F\]AlF-FAPI-74 PET/CT leads to changes in diagnostic work-up determined by the local MDT meetings, including: * The number of additional biopsies or longitudinal imaging; * The number of changes in extent of surgery

Secondary Outcome Measures

Name	Time	Method
Incidental findings	Immediately after completion of clinical staging. Clinical staging consists of FAPI-PET/CT, additional diagnostics following FAPI-PET/CT (if necessary to confirm suspect lesions on FAPI-PET/CT) and/or diagnostic laparoscopy	Proportion of patients with relevant incidental findings (e.g. second primary tumors)
Impact of incidental and/or non-specific findings	Immediately after completion of clinical staging. Clinical staging consists of FAPI-PET/CT, additional diagnostics following FAPI-PET/CT (if necessary to confirm suspect lesions on FAPI-PET/CT) and/or diagnostic laparoscopy.	Patients' extra burden of undergoing additional diagnostics due to incidental and/or non-specific \[18F\]AlF-FAPI-74 PET/CT findings using a Patient Reported Experience Measure (PREM) questionnaire. This includes questions designed to capture the differences in patient burden between imaging with FAPI-PET/CT and staging laparoscopy. The scale ranges from 1 (strongly agree/not annoying at all) to 5 (strongly disagree/very annoying). A higher score represents a worse outcome.
Diagnostic performance	Immediately after completion of clinical staging. Clinical staging consists of FAPI-PET/CT, additional diagnostics following FAPI-PET/CT (if necessary to confirm suspect lesions on FAPI-PET/CT) and/or diagnostic laparoscopy	Diagnostic performance measured in sensitivity, specificity, diagnostic accuracy, positive predictive value and negative predictive value using histopathologic tumor tissue collected during biopsy, staging laparoscopy and follow-up imaging as reference test
FAPI uptake and histopathological tumor scores	Immediately after staging laparoscopy	Correlation between PCI-regional FAPI uptake and PCI-regional histopathological tumor scores (this is done only for LUMC patients).
TSR, FAP expression and FAPI-PET/CT signals	Immediately after gastrectomy or immediately after staging laparoscopy (if no gastrectomy is performed)	Analysis of TSR and FAP expression and correlation to \[18F\]AlF-FAPI-74 PET/CT signal
Diagnostic time delay due to extra investigation	Immediately after completion of clinical staging (after post-diagnostic MDT). Clinical staging consists of FAPI-PET/CT, additional diagnostics following FAPI-PET/CT (if necessary to confirm suspect lesions on FAPI-PET/CT) and/or diagnostic laparoscopy.	Time between pre-diagnostic and post-diagnostic MDT meetings
Safety data regarding clinical use of [18F]FAPI-74 PET/CT	From start of injection of [18F]FAPI-74 up to 24 hours after administration.	The occurrence, type, and severity of (serious) adverse events
FAP-expression	Baseline, before study procedure (for D1D2/CRITICS samples) and immediately after gastrectomy or immediately after staging laparoscopy (if no gastrectomy is performed, for PLASTIC-3 patients)	Expression of CAF content as measured by tumor-stroma ratio (TSR) on tissue samples from D1D2/CRITICS and relation with FAP expression. TSR according to van Pelt and Mesker et al.
FAP expressing CAF subsets	Immediately after gastrectomy or immediately after staging laparoscopy (if no gastrectomy is performed)	Analysis of all FAP expressing CAF subsets in obtained patient samples using imaging mass cytometry
Patient burden	Immediately after completion of clinical staging (after post-diagnostic MDT). Clinical staging consists of FAPI-PET/CT, additional diagnostics following FAPI-PET/CT (if necessary to confirm suspect lesions on FAPI-PET/CT) and/or diagnostic laparoscopy.	Patient burden using a developed patient reported experience measure (PREM) questionnaire
FAPI-PET based PCI scores	Immediately after staging laparoscopy, which takes place after FAPI-PET/CT.	Correlation between \[18F\]AlF-FAPI-74 PET-based Peritoneal Cancer Index (PCI) scores and staging laparoscopy based PCI scores as a reference standard for 'true' intraperitoneal tumor load (this is done only for the LUMC patients).
Costs of [18F]FAPI-74 PET/CT	At 3 and 12 months after completion of clinical staging	Costs of \[18F\]AlF- FAPI-74 PET/CT compared with staging laparoscopy compared to PLASTIC for patients who received SL only, using the SL bottom-costing approach numbers from the PLASTIC-cost analysis study and resource use questionnaires
Health-related quality of life	At enrollment, after completion of clinical staging but before starting treatment, after completion of clinical staging at 3, 6, 9 and 12 months	Quality of life as measured using the EQ-5D5L questionnaire and compared to PLASTIC. This comprises 5 dimensions and each dimension has five response levels, from no problems to unable to/extreme problems. Health states can be summarised using a 5 digit code (one digit for each dimension, no problems is coded as one and extreme problems as 5 and everything in between, e.g. 21111) or represented by a single summary number (index value), through which QALY's can be calculated. The index is derived by applying a formula that attaches values (weights) to each of the levels in each dimension.

Trial Locations

Locations (10)

ZGT; 🇳🇱 Almelo, Netherlands

Amsterdam UMC; 🇳🇱 Amsterdam, Netherlands

Netherlands Cancer Institute - Antoni van Leeuwenhoek; 🇳🇱 Amsterdam, Netherlands

Rijnstate; 🇳🇱 Arnhem, Netherlands

Catharina Ziekenhuis; 🇳🇱 Eindhoven, Netherlands

Zuyderland; 🇳🇱 Geleen, Netherlands

UMC Groningen; 🇳🇱 Groningen, Netherlands

Leids Universitair Medisch Centrum; 🇳🇱 Leiden, Netherlands

Erasmus MC; 🇳🇱 Rotterdam, Netherlands

UMC Utrecht; 🇳🇱 Utrecht, Netherlands