Table 2.

Univariate and multivariate analysis of prognostic factors of stent patency in 135 patients with malignant biliary obstruction

			Univariate analysis		Multivariate analysis
Variable*		No. of cases	Median stent patency (95%CI)*	p†	HR (95%CI)	p$
Gender	Male	82	6.1 (5.4–6.8)	0.941
	Female	53	6.3 (4.1–8.5)
Age (year)	≥ 65	56	5.6 (4.3–6.9)	0.672
	< 65	79	6.5 (5.6–7.4)
EGCO PS +	≥ 2	48	5.6 (4.4–6.8)	0.193
	< 2	87	6.5 (5.5–7.5)
Bismuth type ‡	III–IV	31	4.3 (3.2–5.4)	0.000	2.778 (1.765, 4.371)	0.000
	I–II	104	6.8 (6.1–7.5)
Distant metastasis	Yes	58	5.7 (4.8–6.6)	0.008	1.708 (1.171, 2.491)	0.005
	No	77	6.7 (5.9–7.5)
CA 125 (U/mL)	> 40	71	5.8 (4.4–7.2)	0.263
	≤ 40	64	6.5 (5.8–7.2)
CA 19-9 (U/mL)	> 40	118	6.3 (5.4–7.2)	0.222
	≤ 40	17	5.9 (4.4–7.4)
Length of stricture (cm)	≥ 4	60	5.2 (4.2–6.2)	0.027	1.727 (1.124, 2.654)	0.013
	< 4	75	6.8 (6.0–7.6)
Length of stent (mm)	> 6	48	5.8 (4.3–7.3)	0.646
	≤ 6	87	6.1 (5.3–6.9)
Stent placement	Following	57	6.1 (4.4–7.8)	0.661
	Synchronising	78	6.1 (5.2–7.0)

*Stent patency data are in months, and the Kaplan–Meier method was used

^†The long-rank test was used

^$Cox regression was used

⁺According to the Toxicity and response criteria of Eastern Cooperative Oncology Group

^‡According to the Bismuth classification of perihilar cholangiocarcinoma

CA125/19-9, carbohydrate antigen 125/19-9