Clutch Cutter knife efficacy in endoscopic submucosal dissection for early gastric neoplasms

Table 1 Characteristics of enrolled patients before propensity score matching

	ESD-C n = 50	ESD-O n = 105	P value	ASD
Age, yr
Mean ± SD	73.1 ± 8.55	72.75 ± 8.04	0.8062	0.0422
Median (range)	74.0 (46–91)	73.0 (52–91)	0.5803
Sex (n)
Male	39	71	0.2561	0.2350
Female	11	34
Underlying disease, positive, n (%)	18 (36.0)	29 (27.6)	0.3501	0.1810
Anti-thrombotic drugs (n)
None or discontinuation	48	102	0.6581	0.0623
Continuation	2	3
Tumor location (n)
Upper third	9	17	0.8201	0.0481
Middle or lower third	41	88
Tumor position (n)
Lessor	21	57	0.7311	0.2670
Others	29	48
Morphology (n)
Flat or depressed	29	63	0.8621	0.0407
Others	21	42
Histology (n)
Undifferentiated	5	1	0.01414	0.4060
Others	45	104
Tumor size (mm)
Mean ± SD	16.89 ± 12.65	20.90 ± 13.30	0.0762	0.3090
Median (range)	13.5 (3–67)	18.0 (3–82)	0.02734
Tumor depth (n)
Mucosa	44	91	1.0001	0.0401
Submucosa	6	14
Ulceration positive, n (%)	7 (14.0)	22 (21.0)	0.3811	0.1840
Operator skill
Experts	34	73	0.8541	0.0329
Trainees	16	32

¹P value was calculated using Fisher’s exact test;

²P value was calculated using a t test;

³P value was calculated using the Mann–Whitney U test;

⁴Significant value. ESD-C: Endoscopic submucosal dissection with Clutch Cutter; ESD-O: Endoscopic submucosal dissection with another end-knife; SD: Standard deviation; ASD: Absolute standardized difference.

Table 2 Matching factors between two groups after propensity score matching

	ESD-C n = 44	ESD-O n = 44	P value	ASD
Variable matching between groups
Age, yr; mean ± SD	73.16 ± 8.59	71.11 ± 8.81	0.2732	0.2360
Sex: Male/female	8/36	6/38	0.7721	0.1250
Underlying disease: No/yes	28/16	29/15	11	0.0476
Anti-thrombotic drugs: No/yes	2/42	3/41	11	0.0983
Tumor location: Upper third/others	7/37	2/42	0.2501	0.3810
Tumor position: Lessor/others	19/25	21/23	0.8311	0.0914
Morphology: Flat or depressed/others	25/19	28/16	0.6631	0.1400
Histology: Undifferentiated/others	0/44	0/44	-	0
Tumor size, mm: mean ± SD	16.89 ± 12.65	20.90 ± 13.30	0.0762	0.3090
Tumor depth: Mucosa/submucosa	Jun-38	Jun-38	11	0
Ulceration, positive	6 (13.6%)	4 (9.1%)	0.7391	0.1440
Operator skill: Expert/trainee	14/30	14/30	11	0

¹P value was calculated using Fisher’s exact test;

²P value was calculated using a t test for continuous data. ESD-C: Endoscopic submucosal dissection with Clutch Cutter; ESD-O: Endoscopic submucosal dissection with another end-knife; SD: Standard deviation; ASD: Absolute standardized difference.

Table 3 Treatment outcomes between two groups after propensity score matching n (%)

	ESD-C n = 44	ESD-O n = 44	P value
Procedure time, min			< 0.00123
Mean ± SD	63.1 ± 41.90	98.41 ± 51.77
Median (range)	49 (9–190)	88.5 (26–290)
En bloc resection	44 (100)	44 (100)	-
Complete resection	44 (100)	44 (100)	-
Curative resection	38 (86.4)	39 (88.6)	0.7301
Perforation	0 (0)	0 (0)	-
Delayed bleeding	1 (2.3)	3 (6.8)	0.6201

¹P value was calculated using Fisher’s exact test;

²P value was calculated using the Mann–Whitney U test;

³Significant value. ESD-C: Endoscopic submucosal dissection with Clutch Cutter; ESD-O: Endoscopic submucosal dissection with another end-knife; SD: Standard deviation.