Fig. 1 Technical steps of endoscopic submucosal dissection (ESD). a Subtle and flat early gastric cancer in the gastric antrum in high definition white-light imaging. b,c The same lesion in blue-light imaging (b) and linked color imaging (c). d Lesion markings seen with dye spray. e Mucosal incision using Dual Knife J (Olympus, Tokyo, Japan). f Submucosal dissection. g The ESD lesion base. h The fully dissected and pinned specimen. Histology from this lesion showed intramucosal carcinoma with clear radial and deep margins.