Table 4. Cox proportional hazards model of survival for surgically resected patients with intrahepatic cholangiocarcinoma.

Characteristics	Hazard ratio	95% hazard ratio confidence interval	P value
Age (years)
18–49	REF	–	–
50–59	1.14	0.31–0.92	0.38
60–69	1.15	0.87–1.54	0.31
70+	1.34*	1.01–1.78	0.04
Gender
Female	REF	–	–
Male	1.20*	1.01–1.42	0.04
Race
Non-Hispanic White	REF	–	–
Black	0.90	0.62–1.30	0.58
Others	0.99	0.78–1.27	0.98
Years of diagnosis
2000–2008	REF	–	–
2009–2014	0.89	0.73–1.08	0.23
Grades
I	REF	–	–
II	1.14	0.83–1.56	0.42
III	1.44*	1.03–2.01	0.03
Missing	1.42*	1.02–1.98	0.04
T stages
I	REF	–	–
II	1.38*	1.08–1.79	0.01
III and IV	2.14*	1.69–2.71	<0.0001
Missing	1.38*	1.07–1.79	0.02
Nodes evaluated
None/unknown	REF	–	–
1–5	0.85	0.40–1.83	0.68
6+	0.66	0.29–1.48	0.32
Lymph node status
None/unknown	REF	–	–
LN−	0.92	0.43–1.96	0.83
LN+	2.31*	1.06–5.04	0.04
Chemotherapy
No/unknown	REF	–	–
Yes	0.94	0.78–1.13	0.50

*, statistically significant. LN, lymph node; REF, reference comparative factor.