Kim’s main research interests are endoscopic imaging (including magnifying endoscopy), endosonography, and endoscopic treatment for gastric cancer and esophageal cancer. To elucidate the long-term safety of endoscopic treatment for esophageal and gastric cancer, a propensity-matching analysis between endoscopic treatment and surgery is on-going. To catch up the early diagnosis and individualized therapy in patients with gastric cancer and esophageal cancer, studies for circulating tumor cells and EMT markers in these patients were already published. Recently, studies about detection of circulating tumor cell, exosome, miRNA, and ctDNA are also on-going. In addition, computer-aided diagnosis algorithms for analyzing gastric subepithelial tumors and early esophageal cancer were recently published. Furthermore, algorithms for differentiation of H. pylori gastritis from normal stomach and prediction of histopathology and invasion depth in early gastric cancer will be also developed based on the deep-learning methods. ORCID 0000-0001-9721-5734