Table 4.

Multivariate cox regression analysis of clinicalpathological characteristics on survival of patients with primary metastatic colorectal adenocarcinoma resection according to different T stages, N stages, tumor location or differentiation grades.

Characteristics	OS		CSS
	HR (95% CI)	P	HR (95% CI)	P
T Stage
T1
No	1 (Reference)*		1 (Reference)
Yes	0.51 (0.39-0.66)	<0.001	0.48 (0.36-0.65)	<0.001
T2
No	1 (Reference)		1 (Reference)
Yes	1.09 (0.71-1.68)	0.512	0.93 (0.60-1.44)	0.740
T3
No	1 (Reference)		1 (Reference)
Yes	0.77 (0.67-0.88)	<0.001	0.76 (0.66-0.87)	<0.001
T4
No	1 (Reference)		1 (Reference)
Yes	0.96 (0.84-1.10)	0.542	0.97 (0.85-1.12)	0.715
Location
Proximal colon
No	1 (Reference)		1 (Reference)
Yes	1.12 (0.97-1.29)	0.121	1.11 (0.95-1.29)	0.177
Distal colon
No	1 (Reference)		1 (Reference)
Yes	0.65 (0.56-0.75)	<0.001	0.65 (0.56-0.75)	<0.001
Rectum
No	1 (Reference)		1 (Reference)
Yes	0.60 (0.52-0.70)	<0.001	0.59 (0.51-0.69)	<0.001
Grade
Well/moderate
No	1 (Reference)		1 (Reference)
Yes	0.62 (0.56-0.70)	<0.001	0.62 (0.55-0.69)	<0.001
Poorly/undifferentiated
No	1 (Reference)		1 (Reference)
Yes	1.04 (0.91-1.18)	0.573	1.03 (0.9-1.18)	0.652
N Stage
N1
No	1 (Reference)		1 (Reference)
Yes	0.76 (0.67-0.85)	<0.001	0.74 (0.65-0.84)	<0.001
N2
No	1 (Reference)		1 (Reference)
Yes	0.63 (0.54-0.74)	<0.001	0.65 (0.55-0.77)	<0.001
N3
No	1 (Reference)		1 (Reference)
Yes	0.90 (0.72-1.13)	0.358	0.89 (0.71-1.13)	0.352
N4
No	1 (Reference)		1 (Reference)
Yes	0.84 (0.55-1.30)	0.440	0.88 (0.56-1.37)	0.564

Abbreviation: OS: Overall survival; CSS: Cause-specific survival. HR: Hazard ratio.

* HR for each clinicalpathological characteristic was based on the first variable as a reference (HR was assumed as 1).