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Preoperative Abdominal Enhanced CT, 18F-FDG PET/CT and 68Ga-FAPI PET/CT in Peritoneal Carcinomatosis of Gastric Cancer

Not Applicable
Conditions
Peritoneal Carcinomatosis
68Ga-FAPI PET/CT
Gastric Cancer
Enhanced CT
18F-FDG PET/CT
Interventions
Diagnostic Test: 68Ga-FAPI PET/CT scan
Registration Number
NCT04778345
Lead Sponsor
Fujian Medical University
Brief Summary

This study aims to explore the value of 68Ga-FAPI PET/CT in the diagnosis of gastric cancer peritoneal carcinomatosis in high-risk patients compared with conventional abdominal enhanced CT and 18F-FDG PET/CT. The patients with gastric adenocarcinoma (cT4/N+/M0-1) will be studied.

Detailed Description

After being informed about the study and potential risks, all patients giving written informed consent will receive 68Ga-FAPI PET/CT on the 2nd day to 1st week of 18F-FDG PET/CT. On PET/CT, omentum, peritoneum, and mesenteric lesions with increased radioactive uptake are defined as suspicious peritoneal carcinomatosis. The number of these positive lesions, the maximum standardized uptake value (SUVmax), median and range will be recorded. Subsequently, the patients will undergo laparoscopic exploration, and if radical resection is assessed, radical gastrectomy (D2 lymph node dissection) will be performed. If a radical resection is not feasible, for patients with peritoneal carcinomatosis detected, one metastasis will be taken for rapid frozen diagnosis. After the peritoneal carcinomatosis is confirmed, the metastases seen under laparoscopy will be matched with the suspicious peritoneal carcinomatosis on the three preoperative imaging examinations. The intraoperative findings are used as the gold standard to compare the detection efficiency of the three imaging examinations for peritoneal carcinomatosis. Patients with unresected tumors will receive 4 cycles of conversion therapy or neoadjuvant therapy. After the treatment, 18F-FDG PET/CT and 68Ga-FAPI PET/CT will be performed again. If necessary, patients will be subjected to a second laparoscopic exploration, and radical gastrectomy (D2 lymph node dissection) will be performed for appropriate patients. If a radical resection is still not feasible, for patients with peritoneal carcinomatosis detected, biopsy of metastases will be performed if necessary.

Recruitment & Eligibility

Status
UNKNOWN
Sex
All
Target Recruitment
72
Inclusion Criteria
  1. Age from 18 to 75 years
  2. Primary gastric adenocarcinoma (papillary, tubular, mucinous, signet ring cell, or poorly differentiated) confirmed pathologically by endoscopic biopsy
  3. The clinical tumor stage before PET/CT scan was evaluated as cT4/N+/M0-1, according to the American Joint Committee on Cancer (AJCC) Cancer Staging Manual Eighth Edition
  4. Performance status of 0 or 1 on Eastern Cooperative Oncology Group scale (ECOG)
  5. American Society of Anesthesiology score (ASA) class I, II, or III
  6. Written informed consent
Exclusion Criteria
  1. Women during pregnancy or breast-feeding
  2. Severe mental disorder
  3. History of previous abdominal inflammatory diseases (such as peritonitis, pancreatitis, cholecystitis, inflammatory bowel disease)
  4. History of unstable angina or myocardial infarction within past six months
  5. History of cerebrovascular accident within past six months
  6. History of continuous systematic administration of corticosteroids within one month
  7. Emergency surgery due to complication (bleeding, obstruction or perforation) caused by gastric cancer
  8. Forced expiratory volume in 1 second (FEV1)<50% of predicted values
  9. History of allergy to tracer agents of PET/CT
  10. History of allergy to contrast agents of CT

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
18F-FDG PET/CT and 68Ga-FAPI PET/CT scan after abdominal enhanced CT68Ga-FAPI PET/CT scanAfter the patient received abdominal enhanced CT, 18F-FDG PET/CT and 68Ga-FAPI PET/CT were further performed. The interval between 18F-FDG PET/CT and 68Ga-FAPI PET/CT was 2 days to 1 week.
Primary Outcome Measures
NameTimeMethod
Maximum standardized uptake value [SUVmax (for PET/CT only)] for peritoneal carcinomatosisOne month after surgery

SUVmax of 68Ga-FAPI PET/CT for peritoneal carcinomatosis in comparison with 18F-FDG PET/CT

Diagnostic efficacy for peritoneal carcinomatosisOne month after surgery

Sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of 68Ga-FAPI PET/CT for peritoneal carcinomatosis in comparison with 18F-FDG PET/CT and abdominal enhanced CT

Secondary Outcome Measures
NameTimeMethod
SUVmax (for PET/CT only) for primary lesionsOne month after surgery

SUVmax of 68Ga-FAPI PET/CT for primary lesions in comparison with 18F-FDG PET/CT

1-year progression-free survival rate12 months

The relationship between three kinds of imaging examination and the patient's 1-year progression-free survival rate

Correlation between the expression of FAP and 68Ga-FAPI uptake in different pathological types of primary lesionsOne month after surgery

Analyzing the correlation between the SUVmax of 68Ga-FAPI in primary lesions with different pathological types and FAP identified by pathological examinations

Predictive value of conversion therapy efficacyOne month after surgery

Predictive value of three kinds of imaging examination for gastric cancer in conversion therapy response assessment

Predictive value for peritoneal carcinomatosis by using radiomic algorithmOne month after surgery

Prediction value of three kinds of imaging examination for peritoneal carcinomatosis by using radiomic algorithm

SUVmax (for PET/CT only) for metastatic lymph nodesOne month after surgery

SUVmax of 68Ga-FAPI PET/CT for metastatic lymph nodes in comparison with 18F-FDG PET/CT

Correlation between the expression of FAP and 68Ga-FAPI uptake in different pathological types of metastatic lymph nodesOne month after surgery

Analyzing the correlation between the SUVmax of 68Ga-FAPI in metastatic lymph nodes with different pathological types and FAP identified by pathological examinations

Diagnostic efficacy for primary lesionsOne month after surgery

Sensitivity, specificity, accuracy, PPV and NPV of 68Ga-FAPI PET/CT for primary lesions in comparison with 18F-FDG PET/CT and abdominal enhanced CT

Diagnostic efficacy for metastatic lymph nodesOne month after surgery

Sensitivity, specificity, accuracy, PPV and NPV of 68Ga-FAPI PET/CT for metastatic lymph nodes in comparison with 18F-FDG PET/CT and abdominal enhanced CT

1-year progression patterns12 months

The relationship between the three types of imaging examinations and the patient's 1-year progression patterns

Correlation between the expression of fibroblast activation protein (FAP) and 68Ga-FAPI uptake in different pathological types of peritoneal carcinomatosisOne month after surgery

Analyzing the correlation between the SUVmax of 68Ga-FAPI in peritoneal carcinomatosis with different pathological types and FAP identified by pathological examinations

Trial Locations

Locations (1)

Department of Gastric Surgery

🇨🇳

Fuzhou, Fujian, China

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