Biomarker Analysis of Tislelizumab Combined With Chemotherapy for Perioperative Treatment of G/GEJ Adenocarcinoma

Predictive Biomarker Analysis and Model Construction of Tislelizumab Combined With Chemotherapy for Perioperative Treatment of G/GEJ Adenocarcinoma: A Single-center, Observational Study

G/GEJ adenocarcinoma is one of the most common malignant tumors in China, ranking the fifth highest incidence and third highest mortality worldwide. Currently, surgical resection is the preferred treatment for G/GEJ adenocarcinoma, while the 5-year survival rate of patients is lower than 25%. Compared with surgical resection, immunotherapy is proved to be able to effectively prolong the survival time of patients. On one hand, with the continuous promotion of immunotherapy drugs, the exploration of neoadjuvant application of immunotherapy in G/GEJ adenocarcinoma has become a hotspot in recent years. It's also on their way that clinical trials of programmed death receptor-1 (PD-1), programmed death ligand-1 (PD-L1) and other immune checkpoints are carried out. On the other hand, the research found that although the curative effect of immune therapy seems better, the present G/GEJ adenocarcinoma immunotherapy marker researches mainly focused on the late stage of the cancer, with few studies of immune markers of neoadjuvant therapy for G/GEJ adenocarcinoma. Additionally, it's not quite feasible for single biomarkers to predict the immune treatment effect precisely. Therefore, combined with clinicopathology and therapeutic effects, this study is aimed to construct the efficacy prediction model of anti-PD-1 antibody together with chemotherapy for G/GEJ adenocarcinoma, by detecting RNA expression. Furthermore, this study will perform drug sensitivity test and bio-molecular test on patient derived organoid model to validate the biomarkers found from biological specimens.

Inclusion Criteria:

1. Aged 18-80 (including 18 and 80);
2. G/GEJ adenocarcinoma confirmed by basic ultrasound gastroscopy, enhanced CT (PET/CT), MRI or diagnostic laparoscopy;
3. Biopsy histologically confirmed adenocarcinoma
4. As assessed by the investigator, patients who are qualified for receiving PD-1 mab combined with chemotherapy neoadjuvant therapy;
5. Patients who volunteer to participate in this study and sign the informed consent, with good compliance and cooperation in the acquisition of biological specimens.

Exclusion Criteria:

1. Patients whose biological specimens do not meet the detection standards;
2. In the judgment of the investigator, the patients with factors that might have caused the study to be terminated.