Management of an occluded biliary metallic stent

Table 1 The causes of occluded self-expandable metallic stent

	Tham et al 1998	Buenoet al 2003	Togawa et al 2008	Rogart et al 2008	Ridtitid et al 2010	Cho et al 2011
No. of patients	152	592	95	90	154	583
No. of patients with SEMS occlusion (uncovered/covered)	44 (44/0)	34 (34/0)	40 (40/0)	27 (23/4)	32 (22/10)	77 (30/47)
Tumor ingrowth (%)	28 (63.6)	20 (58.8)	36 (90)	19 (70.4)	25 (78.1)	53 (68.8)
Tumor overgrowth (%)	3 (6.8)	9 (26.5)	3 (7.5)	3 (11.1)	3 (9.4)	9 (11.7)
Sludge/debris (%)	8 (18.2)	5 (14.7)	1 (2.5)	5 (18.5)	51 (15.6)	8 (10.4)
Others	Hyperplasia 3	-	-	-	Migration 4	Compression/blood clot/migration 7
	Undefined 2

¹With tumor overgrowth.

Table 2 The patency time of second drainage and patient survival

	Tham et al 1998	Bueno et al 2003	Togawa et al 2008	Rogart et al 2008	Ridtitid et al 2010	Cho et al 2011
No. of SEMS occlusion	44	34	40	27	32	77
Type of initial SEMS (patients)
Covered SEMS	0	0	0	4	10	47
Uncovered SEMS	44	34	40	23	22	30
Initial stent patency (d): total				118a	60-150a
Covered SEMS	NA	NA	NA	NA	NA	189
Uncovered SEMS	102	125	153	NA	NA	132
Type of second drainage (patients)
Covered SEMS	0	0	26	9	4	40
Uncovered SEMS	19	4	7	5	10	26
Plastic stent	20	24	7	11	1	11
Mechanical cleaning	5	6	0	2	0	0
PTBD	0	0	0	0	7	0
Second drainage patency (median, d)
Covered SEMS	NA	NA	220e	214b	NA	138c
Uncovered SEMS	75	192	141e	54	100	109
Plastic stent	90	90	58e	66	60	88
Mechanical cleaning	34	21	NA	43	NA	NA
PTBD	NA	NA	NA	NA	75	NA
Survival (d)
Covered SEMS	NA	NA	NA	227	NA	440d
Uncovered SEMS	70	NA	NA	389	230f	243
Plastic stent	98	NA	NA	188	130	296
Mechanical cleaning	34	NA	NA	194	NA	NA
PTBD	NA	NA	NA	NA	150	NA

NA: Not available;

^aOverall initial stent patency (d);

^bP < 0.05 for SEMS vs PS and mechanical cleaning;

^cP < 0.05 for covered SEMS vs PS;

^dP < 0.001 for covered SEMS vs uncovered SEMS;

^eMean patency time (d);

^fP < 0.05 for SEMS vs PS and PTBD. SEMS: Self-expandable metallic stent; PTBD: Percutaneous transhepatic biliary drainage; PS: Plastic stent.

Table 3 Incremental cost-effectiveness ratio analysis of a second self-expandable metallic stent vs plastic stent

Studies	n	Approximate cost of each procedure (US $)		Mean number of ERCPs		ICER (US $)
		PS	SEMS	PS	SEMS
Tham et al[14] 1998	38	1044	1956	1.44	1.31	7015
Rogart et al[17] 2008	27	2289	3807	1.27	0.89	1518
Ridtitid et al[18] 2010	32	460	1500	2	2.45	2311

ICER: Incremental cost-effectiveness ratio; ERCP: Endoscopic retrograde cholangiopancreatography; SEMS: Self-expandable metallic stent; PS: Plastic stent.