Narrow-band imaging-modified Kyoto score predicts pathological upgrading after endoscopic submucosal dissection in gastric intraepithelial neoplasia

Table 1 Components of both the conventional and narrow-band imaging-modified Kyoto classification scores

Component	Conventional score	NBI-modified score	Scoring range
Atrophy	0 = none or closed-type (C1); 1 = closed-type (C2 or C3); 2 = open-type (O1-O3)	Same as the conventional Kyoto score	0-2
Intestinal metaplasia	0 = none; 1 = confined to the antrum; 2 = extending to the corpus	IM identified by LBC, WOS, and/or tubulovillous or villous microsurface patterns under NBI-ME: 0 = none; 1 = focal involvement (≤ 30%); 2 = extensive involvement (> 30%)	0-2
Diffuse redness	0 = absent diffuse redness with clearly visible RAC; 1 = mild diffuse redness with partially visible or blurred RAC; 2 = severe diffuse redness with absent or invisible RAC	Same as the conventional Kyoto score	0-2
Enlarged folds	0 = < 5 mm; 1 = ≥ 5 mm	Same as the conventional Kyoto score	0-1
Nodularity	0 = absent; 1 = present	Same as the conventional Kyoto score	0-1
Total score	8	8	0-8

In the narrow-band imaging-modified Kyoto score, only the intestinal metaplasia component was modified using narrow-band imaging magnifying endoscopy-based assessment; the other four components retained the original Kyoto classification criteria. The 30% threshold for grading the extent of intestinal metaplasia followed the convention established by the Endoscopic Grading of Gastric Intestinal Metaplasia system. NBI: Narrow-band imaging; IM: Intestinal metaplasia; LBC: Light blue crest; WOS: White opaque substance; NBI-ME: Narrow-band imaging magnifying endoscopy; RAC: Regular arrangement of collecting venules.