Usefulness of the clip-flap method of endoscopic submucosal dissection: A randomized controlled trial

Table 1 Characteristics of patients scheduled to undergo endoscopic submucosal dissection between those with or without endoclip

	Total	Conventional group	Clip-flap group	P value
Number (n)	104	55	49
Age (yr)	70.1 ± 8.3	69.0 ± 9.5	71.2 ± 6.5	0.17
Sex (male : female)	80:24	42:13	38:11	0.89
Body weight (kg)	59.0 ± 11.2	58.0 ± 11.0	60.2 ± 11.5	0.34
BMI (kg/m2)	22.2 ± 3.1	21.7 ± 2.9	22.8 ± 3.3	0.08
Drugs, n (%)
Anticoagulants	19 (18.3)	11(20.0)	8 (16.3)	0.63
Antihypertensive dugs	56 (53.8)	25 (45.5)	31 (63.3)	0.07
Oral hypoglycemics	16 (15.4)	8 (14.5)	8 (16.3)	0.80
Cholesterol-lowering agents	25 (24.0)	13 (23.6)	12 (24.5)	0.91
H. pylori infection (positive)	36 (34.6)	16 (29.1)	20 (40.8)	0.21
Hemodialysis, n (%)	0 (0)	0 (0)	0 (0)	-
Kyoto classification of gastric mucosa
Atrophy (A0:A1:A2)	3:7:94	2:4:49	1:3:45	0.86
Intestinal metaplasia (IM0:IM1:IM2)	8:36:60	5:15:35	3:21:25	0.24
Diffuse redness (DR0:DR1 :DR2)	47:24:33	26:13:16	21:11:17	0.83
Tumor
Histological diagnosis (adenoma/cancer)	9/95	6/49	3/46	0.39
Differentiation (tub1 + tub2/por + sig)	92/3	48/1	44/2	0.52
Depth (m/sm)	82/13	42/7	40/6	0.86
Location (upper third/middle/lower)	10/37/57	7/20/28	3/17/29	0.47
Major axis of tumor (mm)	18.5 ± 13.4	17.5 ± 11.8	19.7 ± 15.1	0.39
ESD
Procedure time (min)	72.6 ± 49.5	70.8 ± 46.2	74.7 ± 53.3	0.69
Area of resected specimen (mm2)	962 1 ± 896.2	884.6 ± 792.1	1006.4 ± 1004.8	0.49
En bloc resection rate (n, %)	104 (100)	55 (100)	49 (100)	-
Curative endoscopic resection rate (n, %)	94 (90.4)	50 (90.9)	44 (89.8)	0.85
Coagulation of vessels at 2nd look (n, %)	28 (26.9)	16 (29.6)	12 (25.0)	0.60
Delayed bleeding (n, %)	4 (3.8)	3 (5.5)	1 (2.0)	0.37
Perforation (n, %)	2 (1.9)	1 (1.8)	1 (2.0)	0.93
Operator
Procedure times (< 50 cases)	83	43	40	0.66

A0: No atrophic pattern; A1: Atrophic patterns with a margin between the non-atrophic fundic mucosa and atrophic mucosa located in the lesser curvature of the stomach; A2: Atrophic patterns; whose margin does not cross the lesser curvature; BMI: Body mass index; DR0: No diffuse erythema; DR1: Mild diffuse erythema; DR2: Severe diffuse erythema; IM0: No intestinal metaplasia; IM1: Intestinal metaplasia within antrum; IM2: Intestinal metaplasia up to corpus; lower: Lower third of the stomach; m: mucosal layer; middle: Middle third of the stomach; por: Poorly differentiated adenocarcinoma; sig: Signet ring cell carcinoma; sm: Submucosal layer; tub1: Well differentiated adenocarcinoma; tub2: Moderately differentiated adenocarcinoma; upper: Upper third of the stomach; ESD: Endoscopic submucosal dissection; H. pylori: Helicobacter pylori.