Gastric Cancer Stage

Gastric retention not only compromises the quality of endoscopic examination but also significantly increases the risk of reflux and aspiration in sedated patients. Aspiration of gastric contents represents a critical anesthesia-related complication during the perioperative period, carrying substantial implications for anesthetic management. With the growing volume of sedated gastroscopy procedures, predicting gastric retention has become an urgent clinical priority. This prospective study aims to establish a standardized gastric residual volume (GRV) grading system to evaluate both the volume of retained gastric contents and its contributing factors in patients undergoing upper gastrointestinal endoscopy. We will systematically assess the impact of demographic characteristics, comorbidities, and medication history on gastric emptying function. This study will facilitate establishment of an endoscopy-based simplified assessment system for gastric retention.

Accurate preoperative assessment of gastric cancer stage guides eligibility for endoscopic resection, extent of gastrectomy and lymphadenectomy, selection for neoadjuvant therapy, and use of staging laparoscopy. Contrast-enhanced CT (CECT) is guideline-endorsed for initial staging, yet performance varies across institutions and readers. This study will evaluate an artificial-intelligence (AI) system that analyzes routine CECT to detect gastric cancer and assign four-class T stage (T1-T4) and N stage (N0-N3) .

Investigators has conducted a series of studies on patient selection for perioperative immunotherapy in locally advanced gastric cancer. Results from prospective single-arm trial (NCT05739045) demonstrated that 21.74% of patients achieved pathological complete response (pCR) after receiving neoadjuvant nivolumab combined with SOX regimen. Notably, investigators identified that the sensitive group exhibited upregulated MHC-II expression in malignant cells at baseline, with enriched pathways including interferon-gamma signaling and MHC class II antigen presentation. The pCR rate was significantly higher in MHC-II positive patients compared to MHC-II negative patients (36.84% vs 11.11%, P=0.038). Subsequent retrospective analyses and another prospective single-arm study focusing on MHC-II positive populations consistently showed superior short-term treatment outcomes with immunotherapy plus chemotherapy in this subgroup. Building upon these preliminary findings from small-scale studies and considering current developments in the field, we are now initiating this multicenter, randomized, double-blind, placebo-controlled phase III clinical trial. The study aims to evaluate the efficacy and safety of tislelizumab combined with chemotherapy versus placebo plus chemotherapy as perioperative treatment for MHC-II positive patients with locally advanced gastric or gastroesophageal junction adenocarcinoma.

Accurate preoperative staging of gastric cancer is of major importance for guiding therapeutic decision-making, preventing both under- and over-treatment. The purpose of this study is to investigate the diagnostic performance of the Multi-parametric magnetic resonance imaging (mpMRI) and dual-energy computed tomography (DECT) in gastric cancer.