Risk factors of lymph node metastasis or lymphovascular invasion for early gastric cancer: a practical and effective predictive model based on international multicenter data

Table 1 Clinicopathological characteristics of EGC patients in the training set and the validation set

Parameter	Training set	Validation set	P-value
	(n = 1460)	(n = 172)
	n (%)	n (%)
Age (mean ± SD)	57.43 ± 11.5	66.6 ± 10.6	< 0.001
Age			< 0.001
≤ 60	815 (55.8)	49 (28.5)
> 60	645 (44.2)	123 (71.5)
Sex			< 0.001
Male	1024 (70.1)	94 (54.7)
Female	436 (29.9)	78 (45.3)
Tumor location			0.004
Upper	242 (16.6)	28 (16.3)
Middle	475 (32.5)	58 (33.7)
Lower	643 (44.0)	86 (50.0)
Overlap^a	100 (6.8)	0 (0)
Tumor size (mm, mean ± SD)	24.7 ± 15.4	27.8 ± 16.2	0.016
Tumor size			< 0.001
≤ 20 mm	850 (58.2)	67 (39.0)
> 20 mm	610 (41.8)	105 (61.0)
Depth of invasion			< 0.001
Mucosa	641 (43.9)	100 (58.1)
Submucosa	819 (56.1)	72 (41.9)
Tumor histological types			< 0.001
Differentiated	502 (34.4)	122 (70.9)
Undifferentiated	958 (65.6)	50 (29.1)
No. of ELNs (mean ± SD)	28.70 ± 11.5	25.70 ± 11.5	0.001
N stage			0.015
N0	1189 (81.4)	153 (89.0)
N+	271 (18.6)	19 (11.0)
Extent of lymphadenectomy			< 0.001
D1	155 (10.6)	28 (16.3)
D1+	209 (14.3)	39 (22.7)
D2	1096 (75.1)	105 (61.0)
LNM/LVI			0.032
Absent	1145 (78.4)	147 (85.5)
Present	315 (21.6)	25 (14.5)

Abbreviations: SD standard deviation, LNM lymph node metastasis, No. of ELNs number of examined lymph nodes, LVI lymphovascular invasion
^aOverlap, tumor invaded two or more regions simultaneously

ISSN: 1471-2407