A single-center, observational study, integrated biomarker analysis of HIPEC combined Programmed cell death 1 /Programmed cell death 1 ligand 1(PD1/PDL1)inhibitor in previously treated patients of advanced gastric cancer with peritoneal metastasis. Tests will be performed on tumor tissue and blood samples, and imaging assessments will be reviewed in order to monitor how well each patient responds to treatment. This is an observational study, so participants will not receive cancer treatment, other than the treatment received as standard of care.
Advanced gastric (gastroesophageal junction) adenocarcinoma confirmed by histology;
Age 18-75 years, Male or Non-pregnant female
Eastern Cooperative Oncology Group(ECOG): 0~1；
Negative for human epidermal growth factor receptor 2(HER-2) by immunocytochemistry or fluorescence in situ hybridization；
Other distal metastases besides peritoneal metastases (e.g., liver, lung, pleural, brain, bone metastases, etc.);
Other patients who were considered unsuitable for inclusion by the researchers;