Table 2. Correlation of clinicopathological characteristics of currently H. pylori – negative gastric cancers with NBI-ME appearance.

	NBI-ME appearance
Characteristic	Gastritis-like (64 lesions)	Conspicuous (130 lesions)	P value
History of eradication therapy: positive/negative	42/22	57/73	0.006
Endoscopic extent of atrophy: mild, moderate/severe1	50/14	55/75	< 0.001
Size: ≤ 10 mm/ > 10 mm	29/35	55/75	0.758
Location:
upper, middle/lower	43/21	67/63	0.046
less/gre, ant, post	34/30	65/65	0.760
Macroscopic type: elevated/depressed	22/42	42/88	0.871
Histological type, predominant: tub1 (low)/tub1 (high), tub2	51/13	68/62	< 0.001
Depth of invasion: mucosa/submucosa	58/6	117/13	1.000
Surface differentiation: positive/negative	39/25	15/115	< 0.001
Non-neoplastic epithelium: positive/negative	26/38	17/113	< 0.001
Histological grade of atrophy: normal, mild, moderate/marked2	38/26	47/83	0.003
Histological grade of intestinal metaplasia: normal, mild, moderate/marked2	58/6	77/53	< 0.001

NBI-ME, narrow-band imaging with magnified endoscopy; less/gre, ant, post, lesser/greater curvature, anterior or posterior wall; tub1 (low/high), well-differentiated tubular adenocarcinoma, low/high grade atypia; tub2, moderately differentiated tubular adenocarcinoma.

¹Endoscopic extent of atrophy was determined according to the Kimura-Takemoto classification ¹⁸: mild, closed-1, closed-2; moderate, closed-3, open-1; severe, open-2, open-3.

²Histological grades of atrophy and intestinal metaplasia were evaluated in the surrounding mucosa adjacent to the cancer according to the updated Sydney system ²⁶.