Table 3. Results of multivariate Cox regression modeling of overall survival and recurrence-free survival in N1a colon cancer.

Characteristics		Overall survival			Disease-free rate
		Hazard ratio	95% CI	P value	Hazard ratio	95% CI	P value
Age	< 75	1.00		0.442	1.00		0.997
	≧ 75	0.98	0.96 ~ 1.02		0.99	0.97 ~ 1.02
Gender	male	1.00		0.384	1.00		0.099
	female	0.92	0.89 ~ 1.12		0.95	0.62 ~1.54
Performance	0~1	1.00		0.949	1.00		0.280
	2	1.07	0.14 ~ 8.07		0.57	0.21 ~ 1.58
Location	right	1.00		0.391	1.00		0.598
	left	0.63	0.33 ~ 1.22	0.171	0.78	0.49 ~ 1.26	0.313
	sigmoid	0.78	0.43 ~ 1.43	0.418	0.86	0.55 ~ 1.35	0.515
Differentiation	well	1.00		0.349	1.00		0.719
	moderate	2.19	0.19 ~ 25.21	0.529	0.55	0.09 ~ 3.45	0.527
	poor	0.75	0.10 ~ 5.57	0.777	0.62	0.19 ~ 2.01	0.428
Tumor depth	T1+2	1.00			1.00		0.125
	T3+4	1.129	0.51 ~ 2.52	0.767	1.48	0.89 ~ 2.44
Invasion	Present	1.08	0.63 ~ 1.89	0.765	0.94	0.62 ~ 1.43	0.783
	Absent	1.00			1.00
CEA level	≦5	1.00			1.00
	> 5	3.42	2.05 ~ 5.73	<0.001	3.28	2.24 ~ 4.81	<0.001
LN sampling number	≧ 12	1.00			1.00
	< 12	2.11	1.28 ~ 3.41	0.007	1.48	0.98 ~ 2.16	0.056
Treatment of chemotherapy	(+)	1.21	0.61 ~ 2.42	0.591	0.69	0.37 ~ 1.31	0.262
	(-)	1.00			1.00