In Vivo Pathological Diagnosis of Esophageal Lesions Using An Endo-Cytoscopy System

Abstract

Background: Recently, some groups have tried to acquire a direct image of histology in vivo gastrointestinal mucosa (virtual histology). Aim: The aim of this study is to observe the endoscopic characteristics of in vivo cells on the surface layer of various esophageal lesions. Patients and Methods: We examined twenty cases of superficial [email protected] , dysplasia, and Barrett's esophageal cancer using an newly developed Endo-cytoscopy system with methylene blue staining. Equipment: An Endo-cytoscopy system (Olympus, prototype) consisting of two flexible endoscopes, 380 cm long and 3.2 mm in diameter, was employed. These endoscopes passed through the instrument channel of the GIF-1T240 (Olympus). The low-magnification type (XEC300) provided 450X magnification and a field of view of 300x300ƒÊm of tissue. The second endoscope was a higher-magnification type (XEC120) that provided 1125X magnification and a field of view of 120x120ƒÊm of tissue. Results: By observing the normal esophageal mucosa using an [email protected] and methylene blue staining, we were able to observe cells on the surface of the squamous epithelium. These cells were arranged homogeneously with a uniform and low nucleus-cytoplasmic ratio. In esophageal cancer, the density of cells was observed to be much higher than in the normal squamous epithelium. Further, the cell distribution was irregular and the cells were extremely heterogeneous with nuclei that differed in staining, size and shape. The nucleus-cytoplasm ratio was also very irregular. In mild dysplasia, surface cells were observed as normal squamous cells. Histological examination of this lesion showed that the atypical cells were limited to the half of the squamous cell layer close to the basement membrane. The superficial layer was covered by normal squamous cells. In the case of Barrett's esophageal cancer, we were able to observe the cells and nuclei of the Barrett's esophageal mucosa. These cells formed a crypt and the cell density was low. In the cancer lesion, the crypt formation was destroyed, and the cell density was high compared with the non-cancerous Barrett's mucosa. The cells had large and darkly stained nuclei compared with part of the Barrett's metaplasia. Conclusions: Observation using the Endo-cytoscopy system allowed us to examine in detail histological alterations in esophageal lesions.