Endoscopic submucosal dissection and hybrid endoscopic submucosal dissection for stage 1 rectal neuroendocrine tumors

Table 1 The characteristics of 84 lesions with rectal neuroendocrine tumors, n (%)

Characteristic	ESD (n = 61)	Hybrid ESD (n = 23)	t/χ2 value	P value
Lesion size, mm	8 (5)	8 (4)	0.842	0.359
Age (year), mean ± SD	45.38 ± 13.15	42.61 ± 14.38	0.800	0.424
Procedure time, minute	46.00 (14.00)	32.00 (15.00)	25.093	< 0.001
Follow-up time, month	24.00 (23.00)	34.00 (32.00)	5.010	0.024
Male	33 (56.89)	12 (57.14)	0.000	0.984
Location
Anus ≤ 5 cm	24 (39.34)	8 (34.78)	0.147	0.701
Anus > 5 cm	37 (60.66)	15 (65.21)
Operator
Specialist	53 (86.89)	17 (73.91)	2.024	0.192
Beginner	8 (13.11)	6 (26.09)
Perforation	1 (1.64)	0 (0.00)	0.382	1.000
Delayed hemorrhage	1 (1.64)	1 (4.35)	0.527	0.475
Histologic grade
G1	55 (90.16)	20 (86.96)	0.672	0.700
G2	6 (9.84)	3 (13.04)
Invasion depth
Mucosa	5 (8.20)	1 (4.35)	0.541	1.000
Submucosa	56 (91.80)	22 (95.65)
En-bloc resection	61 (100.00)	23 (100.00)
R0 resection	53 (86.89)	20 (86.96)	0.000	1.000
Vascular invasion	0 (0.00)	1 (4.35)	2.684	0.274
Recurrence	0 (0.00)	0 (0.00)

ESD: Endoscopic submucosal dissection.

Table 2 Outcomes between endoscopic submucosal dissection and hybrid endoscopic submucosal dissection groups according to lesion size, n (%)

Characteristic	1A (< 10 mm, n = 56)				1B (10-20 mm, n = 28)
	ESD (n = 41)	Hybrid ESD (n = 15)	t/χ2 value	P value	ESD (n = 20)	Hybrid ESD (n = 8)	t/χ2 value	P value
Procedure time, minute	44.00 (16.00)	30.00 (13.00)	14.905	< 0.001	50.50 (10.00)	33.00 (20.00)	11.471	< 0.001
Follow-up time, month	22.00 (24.00)	30.00 (27.00)	1.426	0.232	26.50 (31.50)	48.00 (22.00)	4.905	0.027
Perforation	0 (0.00)	0 (0.00)	/	/	1 (5.00)	0 (0.00)	0.415	1.000
Delayed hemorrhage	1 (2.43)	0 (0.00)	0.373	1.000	0 (0.00)	1 (12.50)	2.593	0.286
En bloc resection	41 (100.00)	15 (100.00)	/	/	20 (100.00)	8 (100.00)	/	/
R0 resection	37 (90.24)	13 (86.67)	0.147	0.654	16 (80.00)	7 (87.50)	0.219	1.000
Recurrence	0 (0.00)	0 (0.00)	/	/	0 (0.00)	0 (0.00)	/	/

ESD: Endoscopic submucosal dissection.

Table 3 Follow-up of the 12 non-curable resection cases

Number	Gender	Age	Size (mm)	Method	Grade	Invasion depth	Salvage therapy	Microscopic examination	Follow-up (month)	Recurrence
1	Male	41	10	ESD	G1	Submucosa	Colonoscopy	/	76	No
2	Female1	20	5	hybrid ESD	G1	Submucosa	Colonoscopy	/	30	No
3	Male	34	10	ESD	G1	Submucosa	Salvage local resection	Negative	24	No
4	Female	46	8	ESD	G1	Submucosa	Salvage radical surgery	Negative	16	No
5	Female	32	6	hybrid ESD	G1	Submucosa	Colonoscopy	/	12	No
6	Male	27	10	ESD	G1	Submucosa	Salvage local resection	Negative	34	No
7	Female	51	15	hybrid ESD	G1	Submucosa	Colonoscopy + biopsy	Negative	38	No
8	Female	31	8	hybrid ESD	G1	Submucosa	Colonoscopy + biopsy	Negative	25	No
9	Male	53	5	ESD	G1	Submucosa	Colonoscopy	/	20	No
10	Male	35	4	ESD	G1	Submucosa	Colonoscopy + biopsy	Negative	29	No
11	Male	36	10	ESD	G1	Submucosa	Colonoscopy + biopsy	Negative	15	No
12	Male	55	5	ESD	G1	Submucosa	Colonoscopy + biopsy	Negative	10	No

¹The case had vascular invasion, and the other 11 cases had positive vertical margins.

Colonoscopy: Colonoscopy follow-up without mucosal biopsy; Colonoscopy + biopsy: Colonoscopy follow-up with mucosal biopsy; ESD: Endoscopic submucosal dissection.

Table 4 Factors associated with non-R0 resection for stage 1 rectal neuroendocrine tumors, n (%)

Characteristic	Non-R0 resection (n = 11)	R0 resection (n = 73)	t/χ2 value	P value
Age (year), mean ± SD	40.09 ± 9.71	45.38 ± 13.88	1.210	0.229
Lesion size, mm	8.00 (5.00)	8.00 (4.00)	0.186	0.666
Procedure time, minute	49.00 (18.00)	42.00 (16.00)	0.721	0.399
Male	7 (63.63)	38 (55.88)	0.232	0.749
Location
Anus ≤ 5 cm	4 (36.36)	28 (38.36)	0.016	1.000
Anus > 5 cm	7 (63.63)	45 (61.64)
Operator
Specialist	6 (54.55)	64 (87.67)	7.553	0.016
Beginner	5 (45.45)	9 (12.33)
Resection method
ESD	8 (72.73)	53 (72.60)	0.000	1.000
Hybrid ESD	3 (27.27)	20 (27.29)
Grade
G1	11 (100.00)	64 (87.67)	1.519	0.598
G2	0 (0.00)	9 (12.33)
Invasion depth
Mucosal	0 (0.00)	6 (8.22)	0.974	1.000
Submucosal	11 (100.00)	67 (91.78)

ESD: Endoscopic submucosal dissection.

Table 5 Univariate and multivariate analysis for factors influencing non-R0 resection

Characteristic	Univariate analysis		Multivariate analysis
	OR (95%CI)	P value	OR (95%CI)	P value
Age (year), mean ± SD	0.97 (0.92-1.02)	0.229	0.97 (0.92-1.03)	0.284
Lesion size, mm	1.03 (0.85-1.25)	0.730	1.01 (0.81-1.26)	0.913
Gender
Male	1.00		1.00
Female	0.72 (0.19-2.70)	0.631	0.74 (0.17-3.23)	0.688
Location
Anus ≤ 5 cm	1.00		1.00
Annus > 5 cm	1.09 (0.29-4.06)	0.899	1.18 (0.28-5.05)	0.824
Operator
Specialist	1.00		1.00
Beginner	5.93 (1.50-23.48)	0.011	7.31 (1.70-31.42)	0.008
Resection method
ESD	1.00		1.00
Hybrid ESD	0.99 (0.24-4.12)	0.993	0.81 (0.16-3.97)	0.792

CI: Confidence interval; OR: Odds ratio; ESD: Endoscopic submucosal dissection.