Table 4. Independent and Significant Clinicopathologic Factors of Poor Overall Survival for Patients with Extrahepatic Cholangiocarcinoma.

Variables	Crude HR (95% CI)	P	Adjusted HR (95% CI)	P
Age (years)
< 65	1 (Reference)		1 (Reference)
≥ 65	1.40 (0.99–1.98)	0.061	1.32 (0.82–2.14)	0.252
Male	0.78 (0.57–1.05)	0.097	1.15 (0.75–1.77)	0.513
Diagnosis
Common bile duct cancer	1 (Reference)		1 (Reference)
Hilar cholangiocarcinoma	2.42 (1.74–3.35)	< 0.001	1.90 (1.09–3.30)	0.023
Histologic differentiation
Well differentiated	1 (Reference)		1 (Reference)
Moderately differentiated	2.35 (1.52–3.65)	< 0.001	2.29 (1.39–3.79)	0.001
Poorly differentiated	3.27 (1.58–6.80)	0.001	1.40 (0.56–3.52)	0.474
AJCC tumor staging
IA	1 (Reference)		1 (Reference)
IB	3.74 (1.63–8.60)	0.002	2.77 (1.15–6.68)	0.023
IIA	4.99 (2.20–11.30)	< 0.001	3.48 (1.45–8.36)	0.005
IIB	7.71 (3.37–17.64)	< 0.001	4.09 (1.61–10.41)	0.003
III	14.31 (5.76–35.55)	< 0.001	2.71 (0.82–8.97)	0.103
IV	23.14 (9.14–58.58)	< 0.001	1.30 (0.29–5.87)	0.731
Treatment modality
Curative intent surgery	1 (Reference)		1 (Reference)
Explorative laparotomy	4.31 (1.55–12.01)	0.005	3.29 (1.12–9.60)	0.030
Medical treatment	6.84 (4.70–9.95)	< 0.001	9.59 (4.92–18.71)	< 0.001
SUVmax of primary tumor
< 5	1 (Reference)		1 (Reference)
≥ 5	1.72 (1.26–2.35)	0.001	1.75 (1.13–2.69)	0.012
SUVmax of regional lymph nodes
< 5	1 (Reference)		1 (Reference)
≥ 5	3.32 (1.89–5.81)	< 0.001	1.76 (0.71–4.37)	0.225
SUVmax of distant metastases
< 5	1 (Reference)		1 (Reference)
≥ 5	4.99 (2.67–9.31)	< 0.001	8.10 (1.96–33.50)	0.004

CI = confidence interval, HR = hazard ratio, SUV_max = maximal standardized uptake value