Double-layered covered stent for the treatment of malignant oesophageal obstructions: Systematic review and meta-analysis

Table 1 Design and patient characteristics of included clinical trials

Publication	Study design	Sample (n)	Age (yr)	Male gender	Adenocarcinoma	Distal esophagus	Tumour length (cm)
Verschuur et al[16], 2006	Prospective	42	65 ± 14	60%	76%	21%	7.8 ± 2.4
	cohort
Kim et al[13], 2009	Prospective	17	68 ± 8	94%	33%	39%	6.1 ± 2.6
	randomized
Park et al[15], 2010	Prospective	32	67 ± 9	75%	N/A	53%	N/A
	cohort
Battersby et al[12], 2012	Prospective	55	72	67%	56%	93%	11.7 ± 2.5
	cohort						(stent length)
Kim et al[14], 2012	Prospective	48	68 ± 11	81%	33%	37%	N/A
	cohort
Mezes et al[11], 2014	Retrospective	56	N/A	61%	38%	55%	N/A
	cohort

N/A: Not available.

Table 2 Event counts of tumour overgrowth, stent migration and complications encountered

Publication	Tumour overgrowth	Stent migration	Food impaction	Reflux esophagitis	Aspiration pneumonia	Esophageal fistula	Perforation	Hemorrhage
Verschuur et al[16], 2006	n = 2	n = 3	-	n = 2	n = 2	-	n = 1	n = 1
Kim et al[13], 2009	-	-	n = 1	-	-	n = 1	-	-
Park et al[15], 2010	n = 5	n = 1	-	n = 4	n = 1	n = 1	-	-
Battersby et al[12], 2012	n = 1	n = 3	6%	8%	3%	0.8%	0.4%	-
Kim et al[14], 2012	n = 13	n = 1	n = 2	n = 13	n = 5	n = 2	-	-
Mezes et al[11], 2014	n = 19	n = 4	-	-	-	n = 1	-	-

Table 3 Summary of the meta-analysis for all outcome measures with the random and fixed effects models

Parameters	Pooled estimates Random (95%CI)	Pooled estimates Fixed (95%CI)	I² heterogeneity
Technical success (%)	97.2 (94.8-98.9)	97.2 (94.9-98.9)	Low (5.8%)
Overall complications (%)	27.6 (20.7-35.2)	28.1 (22.8-33.8)	Moderate (41.9%)
Dysphagia score improvement (0-4)	-2.00 [-2.29-(-1.72)]	-1.94 [-2.04-(-1.84)]	High (87.0%)
Migration (%)	4.7 (2.5–7.7)	4.7 (2.5–7.7)	Low (0.0%)
Overgrowth (%)	11.2 (3.7–22.1)	12.3 (8.5–16.6)	High (82.2%)