Comparison between uncovered and covered self-expandable metal stent placement in malignant duodenal obstruction

Table 1 Baseline characteristics

	Stent type		P value
	Uncovered(n = 38)	Covered(n = 29)
Age (yr)	68.9 ± 10.2	68.5 ± 11.2	0.860
Sex (M/F)	18/20 (47.4/52.6)	11/18 (37.9/62.1)	0.440
ECOG PS (0/1/2/3/4)	0/9/16/9/4	0/5/10/8/6	0.2031
Previous treatment
Operation	6 (9.0)	5 (7.5)	1.000
Chemotherapy	10 (14.9)	5 (7.5)	0.377
Previous biliary drainage
PTBD	5 (13.2)	7 (24.1)	0.246
ERBD	19 (50.0)	8 (27.6)	0.064
PTBD and ERBD	5 (13.2)	0 (0.0)	0.064
Underlying malignancy			0.4231
Pancreatic cancer	22 (32.8)	9 (13.4)
Bile duct cancer	4 (6.0)	8 (11.9)
Gallbladder cancer	4 (6.0)	5 (7.5)
Ampullary cancer	3 (4.5)	2 (3.0)
Duodenal cancer	1 (1.5)	3 (4.5)
Hepatocellular carcinoma	1 (1.5)	1 (1.5)
Others	3 (4.5)	1 (1.5)
Cancer stage			0.3351
I	1 (2.6)	1 (3.4)
II	3 (7.9)	5 (17.2)
III	2 (5.3)	1 (3.4)
IV	32 (84.2)	22 (75.9)
Stent diameter (mm)	19.8 ± 0.55	19.4 ± 0.92	0.699
Stent length (mm)	99.5 ± 17.1	101.4 ± 14.3	0.688
Stent number			0.256
1 stent	35 (53.0)	28 (42.4)
2 stents	3 (4.5)	0 (0.0)
Median time interval to intervention from	96.5 (3-803)	118.0 (1-2930)	0.699
Initial diagnosis (d)
Chemotherapy after procedure	11 (28.9)	5 (17.2)	0.265
Median duration of follow-up (d)	71 (8-592)	60 (9-827)	0.411

¹Linear by linear association. Values are presented as n (%), mean ± SD, or d (range). ECOG PS: Eastern cooperative oncology group performance status; PTBD: Percutaneous biliary drainage; ERBD: Endoscopic retrograde biliary drainage.