Novel Endoscopic Imaging Techniques toward in vivo Observation of Living Cancer Cells in the Gastrointestinal Tract

Recent advances in endoscopic imaging technology have enabled the visualization of cellular-level microstructures of early-stage cancer and its precursors. Chromoendoscopy, magnifying endoscopy, endoscopic optical coherent tomography (EOCT) spectroscopy, and various combinations of these technologies, are all important for the recognition of small and unclear lesions. In order to observe cancer cells in vivo two types of ultra-high magnifying endoscope--'laser-scanning confocal laser-scanning endoscopy series' and 'contact endoscopy series'--that have a maximum of >1,000 times magnifying power have been developed. The use of these endoscopes has allowed the generation of high quality images of both living cancer cells and normal cells in the gastrointestinal tract. In particular, clear images of cells and their nuclei, equivalent to the high quality that is possible with conventional cytology, have been produced. These novel imaging technologies may make in vivo histological diagnosis by virtual histology possible.