Introduction

LASEREO is an endoscope system equipped with the laser light source, illuminates lesions more clearly. It consists two kinds of wavelengths, 410 nm and 450 nm and changes the ratio of them. The laser endoscopic system has the advanced image-enhanced function including linked color imaging (LCI). The LCI shows us color enhanced images. With LCI, the pale red appears cream-like color and the darker red appears brighter red. Thus, they are much easier to indicate. Creating clearer contrast and emphasizing gastritis LCI makes gastritis more diagnosable and has ability to divide gastric mucosa into three types depending upon infectious states of H. pylori; non-gastritis, active gastritis, and inactive gastritis based on the Kyoto classification of gastritis. Using LCI improves the accuracy of identifying diffuse redness of mucosa caused by H. pylori infection. The redness in the LCI image appears crimson color in H. pylori positive patients while mucosa appears apricot color in H. pylori negative patients. When we use LCI to observe intestinal metaplasia and map-like redness, one of the risk factors of gastric cancer, it appears as lavender color. Demonstrating higher capability in detecting neoplasm LCI shows significantly higher capability of detecting neoplasm. We conducted a prospective, multicenter, randomized, controlled trial (LCI-FIND) and found that the LCI improves the detection rate of upper gastrointestinal neoplasms. In this study, we compared capability of LCI to WLI in detecting neoplasm. Primary endpoint was the percentage of patients diagnosed as having a neoplastic lesion in in the pharynx, esophagus or stomach in each of the WLI and LCI groups. LCI shows significantly higher capability of detecting neoplasm, 8.0% in LCI and 4.8% in WLI. Moreover, LCI is highly capable of detecting gastric cancer even after eradications. Conclusion As conclusion, as our large-scale study demonstrated, LCI is very effective in detecting neoplastic lesions in upper GI comparing with WLI. Therefore, the use of LCI is highly recommended to screen upper GI cancers.