Color Features on Linked Color Imaging and Histology of Early Gastric Cancer in Previously Helicobacter pylori-Infected Stomachs

INTRODUCTION: Linked color imaging (LCI) enhances subtle mucosal color differences and may facilitate the detection of early gastric cancer (EGC), particularly in Helicobacter pylori (H. pylori)-eradicated stomachs. However, the histological basis underlying LCI-derived color changes remains incompletely understood. METHODS: We retrospectively analyzed 32 patients with differentiated-type intramucosal EGC in previously H. pylori-infected stomachs who underwent endoscopic submucosal dissection. Color values obtained by white-light imaging (WLI) and LCI were quantified using the CIE 1976 L*a*b* color space. Histological parameters, including superficial vascular density, glandular density, mucosal thickness, and the proportion of intestinal metaplasia (IM), were evaluated in cancerous tissue and adjacent noncancerous mucosa. Associations between endoscopic color values and histological findings were assessed using Spearman's rank correlation. RESULTS: LCI significantly increased the color difference (ΔE) between cancerous lesions and adjacent noncancerous mucosa compared with WLI (p < 0.001). Under LCI, a* values showed a moderate positive correlation with superficial vascular density (ρ = 0.39, p < 0.001), particularly within the 0-100 μm layer (ρ = 0.41, p < 0.001). LCI b* values demonstrated a moderate negative correlation with the proportion of IM in the adjacent noncancerous mucosa (ρ = -0.49, p < 0.001), with significantly lower b* values observed in cases with severe IM. CONCLUSION: LCI-derived color values are associated with superficial vascularity in EGC and IM in the background mucosa of previously H. pylori-infected stomachs. These findings provide histological insight into the color characteristics observed with LCI.