Table 1.

Risk factor for lymph node metastasis in patients with submucosal invasive colorectal cancer

		Lymph node involvement		P-value
		No (n = 47)	Yes (n = 8)	Univariate	Multivariate
Age	Mean ± S.D.	60.8 ± 9.7	64.0 ± 8.9	0.381
Sex	male	29 (61.7 %)	5 (62.5 %)
	female	18 (38.3 %)	3 (37.5 %)	0.966
Tumor location	Rt. Sided colon‡	6 (12.8 %)	2 (25.0 %)
	Lt. Sided colon§	22 (46.8 %)	4 (50.0 %)
	Rectum	19 (40.4 %)	2 (25.0 %)	0.345
Macroscopic shape of	Ip	23 (48.9 %)	3 (37.5 %)
tumor	Isp	9 (19.1 %)	1 (12.5 %)
	Is	12 (25.5 %)	3 (37.5 %)	0.485
Tumor size	≤ 2.3 cm	20 (42.6 %)	5 (62.5 %)
	> 2.3 cm	19 (40.4 %)	2 (25.0 %)	0.428
Circumference ratio†	≤ 1/4	26 (55.3 %)	6 (75.0 %)
	1/4 < or ≤ 2/4	17 (36.2 %)	2 (25.0 %)
	2/4 < or ≤ 3/4	1 (2.1 %)	0
	> 3/4	0	0	0.375
Depth of invasion (μm)	< 1000	1 (2.1 %)	0
	1000 ≤ or < 2000	6 (12.8 %)	2 (25.0 %)
	2000 ≤ or < 3000	10 (21.3 %)	0
	3000 ≤	23 (48.9 %)	4 (50.0 %)	0.435	0.282
Depth of invasion (by	Sm1	12 (25.5 %)	2 (25.0 %)
Kudo’s classification)	Sm2	17 (36.2 %)	1 (12.5 %)
	Sm3	10 (21.3 %)	3 (37.5 %)	0.364	0.063
Differentiation	well	21 (44.7 %)	1 (12.5 %)
	moderately	21 (44.7 %)	6 (75.0 %)
	poorly	0	0	0.112	0.856
Lymphovascular	Absent	37 (78.7 %)	4 (50.0 %)
invasion	Present	5 (10.6 %)	2 (25.5 %)	0.206	0.232
Tumor budding	Absent	23 (48.9 %)	1 (12.5 %)
	Present	15 (31.9 %)	5 (75.0 %)	0.047	0.042
Microacinar structure	Absent	29 (61.7 %)	3 (37.5 %)
	Present	9 (19.1 %)	3 (37.5 %)	0.179	0.247

† = including cecum, ascending, hepatic flexure, and proximal transverse colon.

‡ = including mid to distal transverse, descending, sigmoid, and rectosigmoid colon.

§ = ratio of the circumference of tumor to luminal circumference.