Table 1.

Patient characteristics

	Control group		Study group		Total
	n = 534	%	n = 537	%	n = 1,071	%
Gender
Male	294	55.1	264	49.2	558	52.1
Female	240	44.9	273	50.8	513	47.9
Age
≤50	51	9.6	51	9.5	102	9.5
51–60	140	26.2	154	28.7	294	27.5
61–70	231	43.3	228	42.5	459	42.9
71–80	112	21.0	104	19.4	216	20.2
Median	64 [23–75]		64 [24–75]		64 [23–75]
PS
0	503	94.2	517	96.3	1,020	95.2
1	31	5.8	20	3.7	51	4.8
Tumor location
Right colon (C, A, T)	199	37.3	218	40.6	417	39.0
Left colon (D, S)	221	41.4	211	39.3	432	40.3
Rs	114	21.3	108	20.1	222	20.7
Operative procedure
Laparoscopic	109	20.4	110	20.5	219	20.4
Laparotomy	425	79.6	427	79.5	852	79.6
Histologic types
Wel	187	35.0	190	35.4	377	35.2
Mod	308	57.7	307	57.2	615	57.4
Por	19	3.6	20	3.7	39	3.6
Muc	20	3.7	18	3.4	38	3.5
Sig	0	0.0	2	0.4	2	0.2
T (TNM 6th)
T1	16	3.0	16	3.0	32	3.0
T2	51	9.6	45	8.4	96	9.0
T3	283	53.0	272	50.7	555	51.8
T4	184	34.5	204	38.0	388	36.2
N (TNM 6th)
N0	69	12.9	75	14.0	144	13.4
N1	347	65.0	352	65.5	699	65.3
N2	118	22.1	110	20.5	228	21.3
Stage (TNM 6th)
I	1	0.2	0	0.0	1	0.1
IIA	2	0.4	1	0.2	3	0.3
IIB	66	12.4	74	13.8	140	13.1
IIIA	59	11.0	57	10.6	116	10.8
IIIB	288	53.9	295	54.9	583	54.4
IIIC	118	22.1	110	20.5	228	21.3
Extent of LN dissection
D2	147	27.5	136	25.3	283	26.4
D3	387	72.5	391	72.8	778	72.6
No. of LN examined
<12	165	30.9	151	28.1	316	29.5
≥12	369	69.1	386	71.9	755	70.5