Real-time in vivo virtual histology of colorectal lesions when using the endocytoscopy system

Background: The histological findings of GI lesions are based on light-microscopic examination of H&E-stained thin-slice specimens. Recently, a concept of optical biopsy has been advocated. A study of the observation of colorectal lesions using endocytoscopy to obtain real-time histological images in vivo during endoscopy was performed. Design: Prospective study. Aim: To evaluate the usefulness of optical biopsy of colorectal lesions with the endocytoscopy (E-C) system. Patients: The subjects were 113 consecutive patients who underwent a complete colonic examination, from April 2003 to March 2004, performed by a single colonoscopist. Setting: Digestive Disease Center of Showa University Northern Yokohama Hospital. Results: With E-C, it was possible to observe lesions at the cellular level and evaluate cellular atypia in addition to structural atypia in vivo. The correlation was statistically significant between the endocytoscopic diagnosis and the histological diagnosis. Limitations: The endocytoscope had to be touched to the target colonic glands. Conclusions: It was possible to distinguish neoplastic from non-neoplastic lesions, and also possible to distinguish invasive cancer from adenoma. 'Ultra-high' magnifying endoscopy, the E-C system, provides real-time histological images in vivo, which correspond well with those of H&E-stained microscopic images.