Early gastric cancer is defined as invasive gastric cancer that invades no more deeply than the submucosa, irrespective of lymph node metastasis (T1, any N). The need for better approaches to the treatment of early gastric cancer has led to the development of advanced endoscopic techniques to diagnosis and resect early gastric cancer. | Journal of military pharmaco-medicine no8-2018 EARLY GASTRIC CANCER: FROM BASIC KNOWLEDGE TO UNDERSTANDING HOW TO FIND IT BY ENDOSCOPY: REVIEW Dao Truong Giang1; Duong Xuan Nhuong1 SUMMARY Early gastric cancer is defined as invasive gastric cancer that invades no more deeply than the submucosa, irrespective of lymph node metastasis (T1, any N). The need for better approaches to the treatment of early gastric cancer has led to the development of advanced endoscopic techniques to diagnosis and resect early gastric cancer. This review aims: To guide gastrointestinal doctor to understand early gastric cancer from basic histologic knowledge and the usefulness of conventional endoscopy to advanced endoscopy to diagnose early gastric cancer. * Keywords: Gastric cancer; Endoscopy. DEFINITION The concept of early gastric cancer (EGC) was originated in Japan in 1962. At that time, an EGC was defined as a neoplasm that could be successfully treated with surgery. EGC is now defined more specifically as an adenocarcinoma that is restricted to mucosa or submucosa, irrespective of lymph node metastasis (T1, any N). These cancers have a significantly better prognosis (approximately 90% five-year survival rate) than do more advanced stages of gastric cancer. In Japan, gastric cancer screening began in the 1960s, and was continued to be the leading cause of cancer mortality. There has been a transition to magnification chromo-endoscopy with indigo-carmine spray in experienced centers in Eastern Asia. In addition, there is variation in screening practices by country and region. Methods used to screen for gastric cancer include endoscopy, H. pylori serology, and serum pepsinogen testing. HISTOLOGICAL CLASSIFICATION Gastric cancers can be classified in a number of ways, according to both histological and macroscopic findings. 1. Lauren classification. Histologically, gastric cancers are classified as intestinal (well-, moderately-, poorlydifferentiated) or diffuse .