Prediction of Neoadjuvant Chemotherapy Efficacy in Locally Advanced Gastric Cancer

Study Overview
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Brief Summary
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This study intends to explore the value of 68Ga-FAPI-04 and 18F-FDG PET/CT in the evaluation of treatment response to neoadjuvant chemotherapy(NAC) for patients with locally advanced gastric cancer(LAGC).

Detailed Description
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Before the start of NAC, baseline 68Ga-FAPI-04 PET/CT and 18F-FDG PET/CT scans will be scheduled in all enrolled patients. Next, the patients with resectable LAGC will receive NAC treatment, surgery will follow 3 6 weeks after finishing NAC. Abdomen 68Ga-FAPI-04 PET/CT and 18F-FDG PET/CT will be scheduled after one cycle of NAC treatment or before surgery. Imaging response measurements will be compared with the histopathological tumor regression grade (TRG) of the resection specimen as gold standard.

Official Title
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A Prospective Study on Predicting the Efficacy of Neoadjuvant Chemotherapy in Locally Advanced Gastric Cancer.

Conditions
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Gastric Cancer

Intervention / Treatment
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* Diagnostic Test: 68Ga-FAPI-04 PET/CT and 18F-FDG PET/CT


Participation Criteria
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Eligibility Criteria
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Inclusion criteria Age between 18-75 years. Histologically confirmed gastric adenocarcinoma through gastroscopy. Resectable gastric cancer. ECOG performance status 0-1. White blood count >4x109/L, Absolute neutrophil count (ANC) >2x109/L, Hemoglobin (Hb)>90g/L, Platelets >100x109/L. Ejection Fraction>50%. Serum bilirubin <1.5x ULN; ALT and AST <1.5x ULN. Serum creatinine ≤1.5x ULN, or GFR> 60ml/min. Agreement to participate in this study with informed consent form. Willingness and ability to comply with the protocol for the duration of the study. No children bearing petential in the next six months before enrollment. Exclusion criteria With second primary malignant diseases in past five years, exceptions include basal cell and squamous cell carcinoma of the skin that have been cured. Known hypersensitivity reaction to chemotherapy drugs or with contraindications. With severe disease or other unsuitable conditions determined by investigators. Inadequate organ function. With uncontrollable diabetic or fasting blood glucose level ≥11 mmol/L on the test-day. With severe mental symptoms, unconscious or unable to complete the examination. Pregnancy or possibly pregnant woman, breastfeeding woman. Lack of compliance.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: PET/CT for prediction of NAC efficacy<br>68Ga-FAPI-04 PET/CT and 18F-FDG PET/CT will be scanned before, during or after NAC. | Diagnostic Test: 68Ga-FAPI-04 PET/CT and 18F-FDG PET/CT<br>* Baseline 68Ga-FAPI-04 PET/CT and 18F-FDG PET/CT scans before NAC followed by abdomen 68Ga-FAPI-04 PET/CT and 18F-FDG PET/CT scans after one cycle of NAC treatment or before surgery.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prediction for NAC efficacy | Predictive value of 68Ga-FAPI PET/CT and 18F-FDG PET/CT for LAGC in NAC response assessment. | Two weeks after surgery | 
| Standardized uptake value(SUV) | SUV of 68Ga-FAPI and 18F-FDG uptake on PET/CT images for primary gastric cancer. | Two weeks after surgery | 
| Target-to-background ratio(TBR) | 68Ga-FAPI and 18F-FDG uptake ratio of primary gastric cancer to mediastinum blood pool on PET/CT images. | Two weeks after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnostic efficacy for metastatic lymph nodes | The sensitivity, specificity, NPV, PPV and accuracy of 68Ga-FAPI PET/CT for metastatic lymph nodes in comparison with those of 18F-FDG PET/CT. | Two weeks after surgery | 
| Disease free survival | Disease free survival | 5 years | 
| Overall survival | Overall survival | 5 years |