Table 1.

Clinicopathological characteristics of the IB and IIA cohort (n = 1,229)

	Group 1	Group 2	Group 3	Group 4
Variables	IIA (n = 552)	T2N0 LVI(+) (IB) (n = 109)	T2N0 LVI(-) (IB) (n = 283)	T1N1 (IB) (n = 285)	p-value
Age (year)	59.3 ± 12.4	63.3 ± 12.2	58.2 ± 12.3	61 ± 12.1	0.001
Sex					0.005
Male	385 (69.7)	76 (69.7)	216 (76.3)	178 (62.5)
Female	167 (30.3)	33 (30.3)	67 (23.7)	107 (37.5)
BMI (kg/m2)	23.8 ± 3.1	23.7 ± 2.5	23.3 ± 3.2	23.7 ± 3.4	0.602
ECOG score					0.407
0 or 1	537 (97.3)	105 (96.3)	272 (96.1)	280 (98.2)
2 or higher	15 (2.7)	4 (3.7)	11 (3.9)	5 (1.8)
Approach					0.000
Open	426 (77.2)	74 (67.9)	234 (82.7)	156 (54.7)
Laparoscopy	118 (21.4)	34 (31.2)	46 (16.3)	122 (42.8)
Robot	8 (1.4)	1 (0.9)	3 (1.1)	7 (2.5)
Extent of gastrectomy					0.001
Total gastrectomy	146 (26.4)	25 (22.9)	66 (23.3)	41 (14.4)
Distal gastrectomy	404 (73.2)	83 (76.1)	215 (76)	244 (85.6)
Proximal gastrectomy	2 (0.4)	1 (0.9)	2 (0.7)	0 (0)
Extent of lymph node dissection					0.000
D1+	106 (19.2)	23 (21.1)	58 (20.5)	96 (33.7)
D2 or more	446 (80.8)	86 (78.9)	225 (79.5)	189 (66.3)
OP time	197.3 ± 52.7	183.7 ± 57.2	195.9 ± 45.6	186.3 ± 55.2	0.093
EBL	145 ± 109.5	124.1 ± 91.9	143.1 ± 122.3	139.8 ± 161.2	0.730
Number of tumor					0.228
Single	530 (96)	101 (92.7)	264 (93.3)	270 (94.7)
Multiple	22 (4)	8 (7.3)	19 (6.7)	15 (5.3)
Tumor size	4.7 ± 2.6	4.3 ± 2.3	3.7 ± 1.8	3.8 ± 2	0.000
Histology					0.008
Differentiated type	246 (44.6)	58 (53.2)	119 (42)	155 (54.4)
Undifferentiated type	305 (55.4)	51 (46.8)	164 (58)	130 (45.6)
Number of harvested lymph nodes	42.3 ± 17.2	40.9 ± 16.8	43.4 ± 18.1	40.4 ± 16	0.175

LVI, lymphovascular invasion; BMI, body mass index; ECOG, Eastern Cooperative Oncology Group; OP, operation; EBL, estimated blood loss