Efficacy of hybrid endoscopic submucosal dissection with SOUTEN in gastric lesions: An ex vivo porcine model basic study

Table 1 Comparison of baseline characteristics of enrolled mock lesions and operators between two groups

	Hybrid ESD (n = 32)	Conventional ESD (n = 32)	P value
Location, n (%)			1
Upper or middle third	15 (46.8)	15 (46.9)
Lower third	17 (53.1)	17 (53.1)
Position, n (%)			1
Lessor curvature	16 (50)	16 (50)
Others	16 (50)	16 (50)
Operator skills			1
Trainee	16 (50)	16 (50)
Expert	16 (50)	16 (50)

P value was calculated by Chi-square test. ESD: Endoscopic submucosal dissection.

Table 2 Comparison of treatment outcomes of endoscopic submucosal dissection between two groups

	Hybrid ESD (n = 32)	Conventional ESD (n = 32)	P value
ESD procedure time, min
Median (IQR)	8.3 (6.6-12.0)	16.2 (9.5-20.1)	< 0.001a
En bloc resection, n (%)	32 (100)	32 (100)
Complete resection, n (%)	30 (93.8)	28 (87.5)	0.67
Perforation, n (%)	0 (0)	1 (3.1)	1
Mucosal incision time, min
Median (IQR)	3.5 (2.5-5.5)	4.2 (2.7-5.3)	0.82
Submucosal dissection time, min
Median (IQR)	5.2 (3.7-6.6)	10.4 (7.0-15.1)	< 0.001a
Resected specimen size, mm2
Median (IQR)	254.3 (201-282.6)	247.3 (201.0-254.3)	0.44
Circumferential length, mm
Median (IQR)	56.5 (50.3-59.7)	55.8 (50.3-56.5)	0.49
Mucosal incision speed, mm/min
Median (IQR)	15.3 (10.8-20.1)	13.0 (10.0-20.3)	0.67
Submucosal dissection speed, mm2/min
Median (IQR)	43.7 (34.6-64.6)	23.8 (17.0-30.1)	< 0.001a
Total injection volume, mL
Median (IQR)	8.3 (6.6-12.0)	16.2 (9.5-20.1)	< 0.001a
Injection volume during mucosal incision, mL
Median (IQR)	5.0 (4.5-7.0)	6.0 (4.8-7.6)	0.40
Injection volume during submucosal dissection, mL
Median (IQR)	1.5 (1.0-2.1)	3.0 (2.4-5.6)	< 0.001a

P value was calculated by chi-square test, Fisher’s exact test and Mann-Whitney U test.

^aSignificant value.

ESD: Endoscopic submucosal dissection; IQR: Interquartile range.

Table 3 Univariate and multivariate analysis for the factors associated with the difficulty of endoscopic submucosal dissection including long procedure time (≥ 20 min), incomplete resection and perforation

	No. of patients	No. of events	Univariate			Multivariate
			OR	95%CI	P value	OR	95%CI	P value
Location
L	34	6	1	Ref	0.25	1	Ref	0.72
U or M	30	9	2.0	0.62-6.5		1.32	0.28-6.3
Position
G or A or P	32	3	1	Ref	0.01a	1	Ref	0.004a
Lessor	32	12	5.8	1.4-23.2		9.9	2.0-71.4
Size
< 250 mm2	31	6	1	Ref	0.45	1	Ref	0.33
≥ 250 mm2	33	9	1.6	0.48-5.1		2.1	0.48-10.1
Operator skill
Expert	32	4	1	Ref	0.05	1	Ref	0.015a
Trainee	32	11	3.7	1.0-13.1		6.2	1.4-37.7
Method
Hybrid ESD	32	3	1	Ref	0.01a	1	Ref	0.002a
Conventional ESD	32	12	5.8	1.4-23.2		10.1	2.2-67.5

^aSignificant value.

ESD: Endoscopic submucosal dissection, OR: Odds ratio, L: Lower third of the stomach; U: Upper third of the stomach; M: Middle third of the stomach; G: Greater curvature; A: Anterior wall; P: Posterior wall.