ABSTRACT
Staging is a subjective assessment of objective progress of gastric cancer by doctors.However, the progress of gastric cancer is the result of tumor breaking through the limitation of immunity according to its inherent characteristics.The subjective evaluation methods are difficult to fully reflect the progress of gastric cancer. From the beginning of the concept of early gastric cancer to the wide application of endoscopic submucosal dissection(ESD) in clinic, the biggest puzzle is how to exclude lymph node metastasis. So far, it has not been satisfactorily solved. Therefore, in all previous Japanese Gastric Cancer Treatment Guidelines, the indications of ESD must be accompanied by the evaluation and treatment after endoscopic resection for possible residual cancer. Comprehending the essence of early gastric cancer and the related factors affecting its progress will help us to improve the quality of treatment for early gastric cancer and benefit patients.