Endoscopic and clinicopathologic characteristics of early gastric cancer with high microsatellite instability

Table 1 Comparison of endoscopic features between the high microsatellite instability and non-high microsatellite instability early gastric cancer groups n (%)

Endoscopic findings	MSI-H EGC (n = 73)	Non-MSI-H EGC(n = 146)	P value
Main gross type			< 0.001
Type I	21 (28.8)	16 (11.0)
Type IIa	23 (31.5)	22 (15.1)
Type IIb	13 (17.8)	48 (32.9)
Type IIc	9 (12.3)	51 (34.9)
Type III	7 (9.6)	9 (6.2)
Location			< 0.001
Antrum	56 (76.7)	66 (45.2)
Body	15 (20.5)	77 (52.7)
Cardia	2 (2.7)	3 (2.1)
Color			0.117
Whitish color	2 (2.7)	9 (6.2)
Normal mucosal color	27 (37.0)	36 (24.7)
Erythematous color	44 (60.3)	101 (69.2)
Demarcation			0.265
Definite	45 (61.6)	101 (69.2)
Obscure	28 (38.4)	45 (30.8)
Intestinal metaplasia			0.138
Absent-to-mild	41 (56.2)	97 (66.4)
Moderate-to-severe	32 (43.8)	49 (33.6)
Mucosal atrophy			0.032
Absent-to-mild	22 (30.1)	66 (45.2)
Moderate-to-severe	51 (69.9)	80 (54.8)
Synchronous lesion	14 (19.2)	12 (8.2)	0.018

MSI-H: High microsatellite instability; EGC: Early gastric cancer.

Table 2 Comparison of clinicopathologic findings between the high microsatellite instability and non-high microsatellite instability early gastric cancer groups n (%)

	MSI-HEGC(n = 73)	Non-MSI-H EGC (n = 146)	P value
Patients characteristics
Sex			0.001
Male	37 (50.7)	108 (74.0)
Female	36 (49.3)	38 (26.0)
Age (yr)	63.4 ± 10.4	56.8 ± 11.1	< 0.001
Pathologic findings
Size (mm)	22.4 ± 15.7	26.5 ± 13.0	0.055
Depth of invasion
Mucosa	27 (37.0)	71 (48.6)	0.102
Submucosa	46 (63.0)	75 (51.4)
Histologic differentiation			0.003
(by WHO classification)
Well differentiated tubular	24 (32.9)	32 (21.9)
Moderately differentiated tubular	30 (41.1)	48 (32.9)
Poorly differentiated tubular	6 (8.2)	29 (19.9)
Signet ring cell	8 (11.0)	43 (24.0)
Mucinous	5 (6.8)	2 (1.4)
Lauren classification			0.017
Intestinal	61 (83.6)	100 (68.5)
Diffuse	12 (16.4)	46 (31.5)
Mucinous component	7 (9.6)	3 (2.1)	0.017
No signet ring cell component	60 (90.4)	116 (79.5)	0.041
Co-existing underlying adenoma	29 (39.7)	29 (19.9)	0.002
Lymphovascular invasion	17 (23.3)	22 (15.1)	0.134
Lymph node metastasis	12 (16.4)	14 (9.6)	0.14
Lymphoid stromal reaction			0.002
Absent-to-mild	49 (74.2)	91 (91.9)
Moderate-to-severe	17 (25.8)	8 (8.1)
Synchronous lesion			0.018
Early gastric cancer	7 (9.6)	5 (4.8)	0.11
Adenoma	7 (9.6)	7 (3.4)	0.163

MSI-H: High microsatellite instability; EGC: Early gastric cancer; WHO: World Health Organization.

Table 3 Logistic regression analysis of endoscopic and clinicopathologic features of high microsatellite instability early gastric cancer

	OR	95% CI		P value
		Lower	Upper
Endoscopic factors
Elevated gross type (I or IIa)	4.38	2.40	8.01	< 0.001
Antral location	3.99	2.12	7.52	< 0.001
Intestinal metaplasia (moderate-to-severe)	1.55	0.87	2.75	0.139
Mucosal atrophy (moderate-to-severe)	1.91	1.05	3.47	0.033
Clinicopathologic factors
Female sex	2.77	1.53	4.99	< 0.001
Age ≥ 70 years	3.30	1.57	6.92	0.002
Histologic differentiation (well or moderately)	2.35	1.27	4.34	0.007
Lauren classification (intestinal type)	2.34	1.15	4.76	0.019
Submucosal invasion	1.61	0.91	2.87	0.103
Less signet ring cell component	2.44	1.02	5.86	0.046
Mucinous component	5.06	1.27	20.17	0.022
Lymph node metastasis	1.86	0.81	4.25	0.144
Lymphovascular invasion	1.71	0.84	3.47	0.137
Lymphoid stromal reaction (moderate-to-severe)	3.95	1.59	9.80	0.003
Co-existing underlying adenoma	2.66	1.43	4.95	0.002
Synchronous EGC or adenoma	2.65	1.16	6.07	0.021

OR: Odds ratios; CI: Confidence intervals; EGC: Early gastric cancer.