The goal of this retrospective observational cohort study is to describe the real-world clinicopathological characteristics, evolving treatment patterns, and long-term oncological outcomes of early gastric cancer (EGC) patients in China, utilizing a large prospective clinical database.

The main questions it aims to answer are:

How do different treatment modalities, including endoscopic resection, laparoscopic surgery, open surgery, and combined laparoscopic-endoscopic approaches, influence the long-term survival (Overall Survival and Disease-Free Survival) and recurrence patterns in Chinese EGC patients? What are the key clinicopathological factors affecting prognosis in this population? This study will retrospectively enroll approximately 5000 patients with histopathologically confirmed gastric adenocarcinoma staged as early gastric cancer (per AJCC 8th edition) from the information database of the National Clinical Research Center for Digestive Diseases. Researchers will systematically collect baseline demographics, treatment details, surgical complications, pathological staging, and longitudinal follow-up data (up to 10 years post-surgery) for all eligible patients. By comparing the short-term safety profiles and long-term survival benefits across different treatment groups and identifying risk factors for recurrence, this study aims to provide high-quality, China-specific evidence to guide standardized and individualized clinical decision-making for early gastric cancer.