Differential analysis of lymph node metastasis in histological mixed-type early gastric carcinoma in the mucosa and submucosa

Table 1 Clinicopathological characteristics of patients with early gastric cancer n (%)

Variable	Value
Age (yr), median ± SD (range)	59.5 ± 12.1 (18-86)
Gender
Male	206 (69.1)
Female	92 (30.9)
Tumor size (cm), median ± SD (range)	2.2 ± 1.2 (0.5-6.0)
Location
U	71 (23.8)
M/L	227 (76.2)
Gross type
Elevated	106 (35.6)
Flat/depressed	192 (64.4)
Depth of invasion
M	165 (55.4)
SM	133 (44.6)
Histological type
Pure D	188 (63.1)
D > U	24 (7.0)
U > D	17 (5.7)
Pure U	69 (23.2)
Lymph node metastasis
Present	43 (14.4)
Absent	255 (85.6)

SD: Standard deviation; U: Upper; M/L: Middle/lower; M: Mucosa; SM: Submucosa; Pure D: Pure differentiated; D: Differentiated components; U: Undifferentiated components; Pure U: Pure undifferentiated.

Table 2 Risk factors for lymph node metastasis in early gastric carcinoma

Variable	Univariate analysis			Multivariate analysis
	OR	95%CI	P value	OR	95%CI	P value
Age (yr)			0.005
≤ 60	1.00
> 60	0.37	0.18-0.74
Gender			0.044
Male	1.00
Female	1.97	1.02-3.82
Size (cm)	1.33	1.04-1.71	0.022			0.154
Location			0.010
U	1.00
M/L	4.85	1.45-16.19
LV invasion			< 0.001
Absent	1.00
Present	18.4	8.31-40.72
Gross type			0.034
Elevated	1.00
Flat/depressed	2.32	1.07-5.04
Ulcer			0.031			0.256
Absent	1.00
Present	2.15	1.07-4.31
H. pylori infection			0.346
Absent	1.00
Present	1.46	0.67-3.19
Depth of invasion			0.001			0.023
Mucosa	1.00
Submucosa	3.41	1.70-6.83		4.58	1.23-16.97
Histological type			0.001			0.054
Pure D	1.00
Pure U	2.99	1.39-6.44	0.005	4.97	1.21-20.39	0.026
Mixed-type	4.45	1.91-10.36	0.001	5.84	1.05-32.61	0.044
Depth of invasion/histological type						0.822

MT: Mixed-type; PU: Pure undifferentiated; PD: Pure differentiated; U: Upper; M/L: Middle/lower; LV: Lymphovascular; LNM: Lymph node metastasis.

Table 3 Clinicopathologic features of mucosa-confined early gastric carcinoma according to histological type n (%)

Variable	MT, n = 17	Pure U, n = 49	Pure D, n = 99	P value	P (Bonferroni corrected)
Age (yr)				0.028	MT vs PU, 0.525
≤ 60	10 (58.8)	33 (67.3)	44 (44.4)		MT vs PD, 0.272
> 60	7 (41.2)	16 (32.7)	55 (55.6)		PU vs PD, 0.009
Gender				0.004	MT vs PU, 0.151
Male	7 (41.2)	30 (61.2)	77 (77.8)		MT vs PD, 0.002
Female	10 (58.8)	19 (38.8)	22 (22.2)		PU vs PD, 0.034
Tumor size (cm)	2.1 ± 1.1	1.9 ± 1.2	1.9 ± 1.2	0.802
Location				0.003	MT vs PU, 0.759
U	1 (5.9)	4 (8.2)	29 (29.3)		MT vs PD, 0.042
M/L	16 (94.1)	45 (91.8)	70 (70.7)		PU vs PD, 0.004
Gross type				< 0.001	MT vs PU, 0.507
Elevated	4 (23.5)	8 (16.3)	51 (51.5)		MT vs PD, 0.033
Flat/depressed	13 (76.5)	41 (83.7)	48 (48.5)		PU vs PD, < 0.001
Ulcer				0.015	MT vs PU, 0.490
Absent	6 (35.3)	22 (44.9)	64 (64.6)		MT vs PD, 0.022
Present	11 (64.7)	27 (55.1)	35 (35.4)		PU vs PD, 0.022
H. pylori infection				0.025	MT vs PU, 0.015
Absent	1 (5.9)	18 (36.7)	22 (22.2)		MT vs PD, 0.119
Present	16 (94.1)	31 (63.3)	77 (77.8)		PU vs PD, 0.061
LV invasion				0.589
Absent	17 (100.0)	47 (95.9)	97 (98.0)
Present	0 (0)	2 (4.1)	2 (2.0)
LNM				0.016	MT vs PU, 0.739
Absent	14 (82.4)	42 (85.7)	96 (97.0)		MT vs PD, 0.012
Present	3 (17.6)	7 (14.3)	3 (3.0)		PU vs PD, 0.010

MT: Mixed-type; PU: Pure undifferentiated; PD: Pure differentiated; U: Upper; M/L: Middle/lower; LV: Lymphovascular; LNM: Lymph node metastasis.

Table 4 Clinicopathologic features of submucosa-invasive early gastric carcinoma according to histological type n (%)

Variable	MT, n = 24	Pure U, n = 20	Pure D, n = 89	P value	P (Bonferroni corrected)
Age (yr)				0.008	MT vs PU, 0.423
≤ 60	14 (58.3)	14 (70.0)	32 (36.0)		MT vs PD, 0.048
> 60	10 (41.7)	6 (30.0)	57 (64.0)		PU vs PD, 0.005
Gender				< 0.001	MT vs PU, 0.069
Male	15 (62.5)	7 (35.0)	70 (78.7)		MT vs PD, 0.104
Female	9 (37.5)	13 (65.0)	19 (21.3)		PU vs PD, < 0.001
Size (cm)	2.6 ± 1.3	2.8 ± 1.4	2.3 ± 1.1	0.166
Location				0.019	MT vs PU, 0.128
U	5 (20.8)	1 (5.0)	31 (34.8)		MT vs PD, 0.191
M/L	19 (79.2)	19 (95.0)	58 (65.2)		PU vs PD, 0.008
Gross type				0.028	MT vs PU, 0.199
Elevated	6 (25.0)	2 (10.0)	35 (39.3)		MT vs PD, 0.195
Flat/depressed	18 (75.0)	18 (90.0)	54 (60.7)		PU vs PD, 0.012
Ulcer				0.369
Absent	5 (20.8)	7 (35.0)	32 (36.0)
Present	19 (79.2)	13 (65.0)	57 (64.0)
H. pylori infection				0.997
Absent	7 (29.2)	6 (30.0)	26 (29.2)
Present	17 (70.8)	14 (70.0)	63 (70.8)
LV invasion				0.325
Absent	15 (62.5)	15 (75.0)	69 (77.5)
Present	9 (37.5)	5 (25.0)	20 (22.5)
LNM				0.008	MT vs PU, 0.375
Absent	15 (62.5)	12 (60.0 )	76 (85.4)		MT vs PD, 0.012
Present	9 (37.5)	8 (40.0)	13 (14.6)		PU vs PD, 0.009

MT: Mixed-type; PU: Pure undifferentiated; PD: Pure differentiated; U: Upper; M/L: Middle/lower; LV: Lymphovascular; LNM: Lymph node metastasis.

Table 5 Risk factors for lymph node metastasis in mucosa-confined early gastric carcinoma

Variable	Univariate analysis			Multivariate analysis
	OR	95%CI	P value	OR	95%CI	P value
Age (yr)			0.082
≤ 60	1.00
> 60	0.31	0.08-1.16
Size (cm)	1.36	0.90-2.06	0.145
Gender			0.005			0.028
Male	1.00			1.00
Female	5.89	1.72-20.17		5.83	1.64-20.70
Location			0.630
U	1.00
M/L	1.47	0.31-6.95
LV invasion			0.013			0.020
Absent	1.00			1.00
Present	13.64	1.75-106.28		13.18	1.39-125.30
Gross type			0.253
Elevated	1.00
Flat/depressed	2.17	0.58-8.22
Ulcer			0.199
Absent	1.00
Present	2.14	0.67-6.85
H. pylori infection			0.244
Absent	1.00
Present	0.50	0.15-1.61
Histological type			0.035			0.106
Pure D	1.00
Pure U	5.33	1.32-21.63	0.019	4.46	0.99-20.00	0.051
Mixed-type	6.86	1.26-37.77	0.026	5.31	0.86-33.01	0.073

PD: Pure differentiated; PU: Pure undifferentiated; U: Upper; M/L: Middle/lower; LV: Lymphovascular.