Diagnostic Ability of Magnifying Blue Light Imaging with a Light Emitting Diode Light Source for Early Gastric Cancer: A Prospective Comparative Study

Abstract

Introduction: An innovative endoscopic system using 4-color light-emitting diodes (LED) was released between 2016 and 2017 in locations that had not approved laser endoscopes for use, including the United States and Europe. Objective: This study compared the diagnostic efficacy between magnifying blue light imaging with an LED light source (LED-BLI) and magnifying blue laser imaging with a laser light source (Laser-BLI) for early gastric cancer (EGC). Methods: In this prospective, single-center, noninferiority study, 80 gastric lesions were evaluated between January 2017 and July 2017. The magnifying findings of gastric lesions – including the demarcation line (DL), microvascular pattern (MVP), and microsurface pattern (MSP) – were evaluated using Laser-BLI and LED-BLI according to the vessel plus surface classification system (VSCS). The primary end point was to determine whether the diagnostic accuracy of LED-BLI for EGC was noninferior to that of conventional Laser-BLI. Results: Overall, we evaluated 79 gastric lesions histopathologically diagnosed as adenocarcinomas from the specimens obtained via endoscopic submucosal dissection. A DL was observed by Laser-BLI and LED-BLI in 98.7% (78/79) and 96.2% (76/79) of EGCs, respectively. The MVP observed using Laser-BLI and LED-BLI was irregular in 92.4% (73/79) and 89.9% (71/79), respectively. The MSP observed using Laser-BLI and LED-BLI was irregular in 83.5% (66/79) and 82.2% (65/79), respectively. According to the VSCS, diagnosable cancers were found in 94.9% (75/79) and 93.7% (74/79) of cases when using Laser-BLI and LED-BLI, respectively (p = 0.73; difference ratio, 1.2%; 95% CI –8.5 to 6.0%). Conclusions: LED-BLI could accurately visualize the DL, MVP, and MSP of EGCs and was not inferior to Laser-BLI. Therefore, LED-BLI can be used to diagnose EGC accurately according to the VSCS-based diagnosis criteria.