Accurate preoperative prediction of risk stratification, treatment response, and survival prognosis in gastric cancer is important for improving clinical treatment decisions, prolonging patient survival, and improving patient quality of life. The purpose of this study is to investigate the performance of the multi-parametric magnetic resonance imaging (mpMRI) and Dual-/Muti-energy CT and photon-counting Detector CT(PCD-CT) in the diagnosis and management of gastric cancer.

Inclusion Criteria:

1. Pathological biopsy confirmed gastric cancer;
2. Surgery: patients undergoing radical gastrectomy. Patients undergoing exploratory abdominal surgery or palliative tumor resection were still included in the study when peritoneal metastasis or adjacent organ invasion was identified intraoperatively and radical surgical resection was not possible.

Exclusion Criteria:

1. Refusal or inability to sign informed consent;
2. CT or MRI images are poor or the focus is small and CT images are not clear;
3. Patients with other tumors complicated with patients with important organ dysfunction.

For patients undergoing radical resection, abdominal exploration or palliative tumor resection, CT scanning and dynamic contrast-enhanced magnetic resonance DCE-MRI scanning shall be completed in GSI mode before operation; for patients undergoing neoadjuvant chemotherapy, CT scanning and dynamic contrast-enhanced magnetic resonance DCE-MRI scanning shall be completed in GSI mode before neoadjuvant chemotherapy at least, and if the above scanning mode can still be used during chemotherapy, it is the best choice.

Signed informed consent form. Patients who were diagnosed with gastric cancer at various medical centers were included in this study