Molecular Imaging of Gastric Cancer Metastatic Lymph Nodes with 99mTc-3PRGD2 Probe.

Inclusion Criteria: 1. Gastric adenocarcinoma was confirmed by histological examination, and the clinical stage was cT2-4N+M0 locally advanced stage; 2. Age 18-75 years old; 3. No previous drug treatment, radiotherapy and other treatments; 4. ECOG 0\~1 points, KPS\>70 points; 5. The baseline blood routine and biochemical indexes of the subjects meet the following criteria: hemoglobin ≥90g/L; Absolute neutrophil count (ANC) ≥1.5×109/L; Platelet ≥100×109/L; ALT, AST≤2.5 times the normal upper limit; ALP≤2.5 times the normal upper limit; Serum total bilirubin \<1.5 times the normal upper limit; Serum creatinine \<1 times the normal upper limit; Serum albumin ≥30g/L; 6. Radical surgical resection (D2 lymph dissection) was performed in all patients. 7. Willing and able to comply with the plan during the study; 8. Provide written informed consent before entering the study screening, and the patient has understood that he or she can withdraw from the study at any time of the study with no loss. Exclusion Criteria: 1. Pregnant or nursing women; 2. Clinically serious (i.e., active) heart disease, such as symptomatic coronary heart disease, NYHA Class II or worse congestive heart failure, or severe arrhythmia requiring medical intervention (see Appendix 12), or a history of myocardial infarction within the last 12 months; 3. Moderate or severe renal impairment \[creatinine clearance equal to or less than 50 ml/min (calculated from Cockroft and Gault equations)\], or serum creatinine \> the upper limit of normal (ULN); 4. Patients with impaired liver function, ALT or AST less than or equal to 3×ULN, total bilirubin less than or equal to 1.5 ×ULN, or with proven Gilbert syndrome at baseline (unbound hyperbilirubinemia), serum albumin greater than or equal to 3.0 g/dL; 5. History of iodine allergy (ICG contains iodine) or allergy to ICG; 6. History of hyperthyroidism; 7. Under the physiological function state of the general elderly, the drug should be administered with caution.