Feasibility of endoscopic treatment and predictors of lymph node metastasis in early gastric cancer

Table 1 Lymph node metastasis risk according to clinical parameters

	Total (n = 1262), n (%)	LNM negative (n = 1080), n (%)	LNM positive (n = 182), n (%)	Univariate OR (95%CI)	P-value
Age (yr)					0.090
≤ 60	628 (49.8)	548 (50.7)	80 (44.0)	1
> 60	634 (50.2)	532 (49.3)	102 (56.0)	1.313 (0.960, 1.800)
Sex					0.239
Male	899 (71.2)	776 (71.9)	123 (67.6)	1
Female	363 (28.8)	304 (28.1)	59 (32.4)	0.817 (0.580, 1.150)
Hypertension					0.554
Absence	958 (75.9)	823 (76.2)	135 (74.2)	1
Presence	304 (24.1)	257 (23.8)	47 (25.8)	1.115 (0.78, 1.60)
Heart disease					0.449
Absence	1146 (90.8)	978 (90.4)	168 (92.3)	1
Presence	116 (9.2)	102 (9.6)	14 (7.7)	0.799 (0.446, 1.430)
Diabetes mellitus					0.933
Absence	1142 (90.5)	977 (90.5)	165 (90.7)	1
Presence	120 (9.5)	103 (9.5)	17 (9.3)	0.977 (0.570, 1.675)
BMI					0.086
≤ 28	1134 (89.9)	964 (89.3)	170 (93.4)	1
> 28	128 (10.1)	116 (10.7)	12 (6.6)	0.587 (0.317, 1.086)
Drinking					0.104
Absence	827 (65.6)	698 (64.7)	129 (70.9)	1
Presence	434 (34.4)	381 (35.3)	53 (29.1)	0.753 (0.534, 1.061)
Smoking					0.138
Absence	692 (54.8)	583 (54.0)	109 (59.9)	1
Presence	570 (45.2)	497 (46.0)	73 (40.1)	0.786 (0.571, 1.082)
Family history					0.872
Absence	1011 (80.1)	866 (80.2)	145 (79.7)	1
Presence	251 (19.9)	214 (19.8)	37 (20.3)	1.033 (0.699, 1.526)
H. pylori infection					0.225
Negative	634 (50.2)	535 (49.5)	99 (54.4)	1
Positive	628 (49.8)	545 (50.5)	83(45.6)	0.823 (0.601, 1.128)
CEA					0.007
Negative	960 (76.1)	836 (77.4)	124 (68.1)	1
Positive	302 (23.9)	244 (22.6)	58 (31.9)	1.603 (1.137, 2.258)

LNM: Lymph node metastasis; OR: Odds ratio; CI: Confidence interval; BMI: Body mass index; H. pylori: Helicobacter pylori; CEA: Carcinoembryonic antigen.

Table 2 Lymph node metastasis in early gastric cancer according to therapeutic indications

	LNM (%)	95%CI	P-value
Absolute indications for ESD	0/90 (0.0)	0%-4.1%	< 0.001
Expanded indications for ESD	4/311 (1.3)	0.35%-3.29%
Surgical indications	178/861 (20.7)	17.75%-23.94%

LNM: Lymph node metastasis; CI: Confidence interval; ESD: Endoscopic submucosal dissection.

Table 3 Lymph node metastasis in early gastric cancer according to the endoscopic submucosal dissection indications

	LNM negative	LNM positive	LNM rate (%)	95%CI	P-value
Ab (n = 90)	90	0	0.0	0%-4.1%	0.021
Ex1 (n = 86)	83	3	3.5	0.75%-10.56%
Ex2 (n = 32)	31	1	3.1	0.08%-17.91%
Ex3 (n = 110)	110	0	0	0%-3.35%
Ex4 (n = 83)	83	0	0	0%-4.44%

Ex1: Differentiated mucosal tumors, ≤ 30 mm in size, without lymphovascular invasion (LVI), and with ulceration. Ex2: Differentiated mucosal tumors, without ulcer and LVI, and of any size. Ex3: Undifferentiated mucosal tumors without ulcer and LVI, and ≤ 20 mm in size. Ex4: Differentiated tumors with SM1 invasion, no LVI, and ≤ 30 mm in size. LNM: Lymph node metastasis; CI: Confidence interval; Ab: Absolute indications for endoscopic submucosal dissection; Ex: Expanded indications for endoscopic submucosal dissection.

Table 4 Lymph node metastasis risk according to endoscopic features

	Total (n = 1262), n (%)	LNM negative (n = 1080), n (%)	LNM positive (n = 182), n (%)	Univariate OR (95%CI)	P-value
Location					0.462
Cardia	46 (3.6)	40 (3.7)	6 (3.3)	1
Fundus/corpora	288 (22.8)	240 (22.2)	48 (26.4)	1.333 (0.535, 3.320)	0.537
Angle/antrum	928 (73.5)	800 (74.1)	128 (70.3)	1.067 (0.443, 2.567)	0.885
Lesion size					< 0.001
Small (≤ 20 mm)	761 (60.3)	680 (63.0)	81 (44.5)	1
Middle (20-30 mm)	285 (22.6)	239 (22.1)	46 (25.3)	1.616 (1.093, 2.388)	0.016
Large (> 30 mm)	216 (17.1)	161 (14.9)	55 (30.2)	2.868 (1.955, 4.207)	< 0.001
Macroscopic type					0.001
0-I(Protruded)	86 (6.8)	71 (6.6)	15 (8.2)	1.712 (0.823, 3.564)	0.147
0-IIa (Elevated)	36 (2.9)	35 (3.2)	1 (0.5)	0.232 (0.030, 1.788)	0.128
0-IIb (Flat)	173 (13.7)	154 (14.3)	19 (10.4)	1
0-IIc (Depressed)	486 (38.5)	432 (40)	54 (29.7)	1.013 (0.582, 1.763)	0.963
0-III (Excavated)	481 (38.1)	388 (35.9)	93 (51.1)	1.943 (1.146, 3.293)	0.012
Number of tumors					0.191
Single	1220 (96.7)	1044 (96.7)	176 (96.7)	1
Multitude	42 (3.3)	36 (3.3)	6 (3.3)	1.724 (0.641, 4.635)
Ulcer					0.013
Absence	558 (44.2)	493 (45.6)	65 (35.7)	1
Presence	704 (55.8)	587 (54.4)	117 (64.3)	1.512 (1.091, 2.094)

LNM: Lymph node metastasis; OR: Odds ratio; CI: Confidence interval.

Table 5 Lymph node metastasis risk according to histopathological characteristics

	Total (n = 1262), n (%)	LNM negative (n = 1080), n (%)	LNM positive (n = 182), n (%)	Univariate OR (95%CI)	P-value
Invasion depth					< 0.001
M	596 (47.2)	565 (52.3)	31 (17.0)	1
SM1	245 (19.4)	197 (18.2)	48 (26.4)	4.441 (2.748, 7.176)	< 0.001
SM2	421 (33.4)	318 (29.4)	103 (56.6)	5.903 (3.862, 9.024)	< 0.001
Differentiation					< 0.001
Differentiated	455 (36.1)	412 (38.1)	43 (23.6)	1
Undifferentiated	807 (63.9)	668 (61.9)	139 (76.4)	1.994 (1.386, 2.867)
Histology					0.019
Pap/Tub/Por	1004 (79.6)	866 (80.2)	138 (75.8)	1
Sig	223 (17.7)	190 (17.6)	33 (18.1)	1.090 (0.723, 1.644)	0.681
Muc	35 (2.8)	24 (2.2)	11 (6.1)	2.876 (1.378, 6.004)	0.005
LVI					< 0.001
Absence	1104 (87.5)	1021 (94.5)	83 (45.6)	1
Presence	158 (12.5)	59 (5.5)	99 (54.4)	20.641 (13.942, 30.559)
Perineural invasion					< 0.001
Absence	1181 (93.6)	1026 (95)	155 (85.2)	1
Presence	81 (6.4)	54 (5.0)	27 (14.8)	3.310 (2.024, 5.413)
Lauren's type					0.003
Intestinal type	500 (39.6)	448 (41.5)	52 (28.6)	1
Diffuse type	399 (31.6)	335 (31.0)	64 (35.2)	1.646 (1.112, 2.437)	0.013
Mixed type	363 (28.8)	297 (27.5)	66 (36.3)	1.915 (1.294, 2.833)	0.001

SM1: Tumor invading the superficial (< 0.5 mm in depth) submucosa. SM2: Tumor invading the deep (> 0.5 mm in depth) submucosa. LNM: Lymph node metastasis; OR: Odds ratio; CI: Confidence interval; M: Tumor confined within the mucosal layer; Pap: Papillary adenocarcinoma; Tub: Tubular adenocarcinoma; Por: Poorly differentiated adenocarcinoma; Sig: Signet ring cell carcinoma; Muc: Mucinous adenocarcinoma; LVI: Lymph-vascular invasion.

Table 6 Multivariate logistic regression analysis of lymph node metastasis in early gastric cancer

Factor	OR (95%CI)	P-value
Lesion size		0.025
Middle lesion size (20-30 mm)	1.230 (0.774, 1.955)	0.380
Large lesion size (>30 mm)	1.900 (1.197, 3.015)	0.006
Histology		0.049
Sig	1.146 (0.698, 1.881)	0.590
Muc	2.823 (1.225, 6.505)	0.015
LVI	15.702 (10.405, 23.695)	< 0.001
Invasion depth		< 0.001
SM1	2.285 (1.317, 3.965)	0.003
SM2	3.230 (2.006, 5.201)	< 0.001

SM1: Invading the superficial (<0.5 mm in depth) submucosa. SM2: Invading the deep (> 0.5 mm in depth) submucosa. LNM: Lymph node metastasis; OR: Odds ratio; CI: Confidence interval; LVI: Lymph-vascular invasion; Sig: Signet ring cell carcinoma; Muc: Mucinous adenocarcinoma.