Primary esophageal Paget’s disease is rare. Only a few case reports have described the intraepithelial papillary capillary loop (IPCL) pattern obtained by magnified Narrow Band Imaging (M-NBI) endoscopy in this rare pathology. This report highlights the usefulness of M-NBI and the successful diagnosis using a large bloc specimen obtained by endoscopic mucosal resection with the cap method (EMR−c). A 53-year-old man was referred to endoscopic examination for dysphagia. The endoscopic image revealed a ring-shaped scarring of the esophagus suggestive for eosinophilic esophagitis. The IPCL pattern by M-NBI endoscopy showed an inflammatory pattern, and the entire epithelium of the esophagus was not stained by Lugol iodine spraying. Based on six biopsies randomly performed, a poorly differentiated adenocarcinoma was diagnosed. Since the M-NBI pattern and the histology were completely different, EMR−c was performed to obtain large bloc specimens for a more detailed diagnosis. The pathological findings revealed extensive Paget’s cells infiltration into the epithelium and multifocal invasion from the mucosa to the submucosal layer with adenocarcinoma. In conclusion, a large bloc specimen by EMR-c might be more useful than a small biopsy for an accurate diagnosis of the rare esophageal Paget’s disease. Key words: Primary Paget’s disease – large bloc specimen – endoscopic mucosal resection. Abbreviations: EMR−c: endoscopic mucosal resection with cap method; IPCL: intraepithelial papillary capillary loop; LVLs: Lugol-voiding lesions; M-NBI: magnified Narrow Band Imaging; PET-CT: Positron-Emission Tomography and Computed Tomography.