Impact of gastric neoplasms location on clinical outcome of patients treated by endoscopic submucosal dissection

Table 1 Comparative outcomes of endoscopic submucosal dissection performance between both gastric segments, n (%)

	Distal stomach, n = 99	Proximal stomach, n = 49	P value
Procedure time, minutes	97.07 ± 42.82	129.08 ± 63.91	0.0011
Overall en bloc resection rate	97 (97.9)	42 (85.7)	0.0016
Overall complete resection rate	93 (93.9)	36 (73.4)	0.0002
Overall curative resection rate	90 (90.9)	32 (65.3)	0.0001
Overall adverse events rate	5 (5.0)	1 (2.0)	0.1911

Table 2 Comparison of procedure time between both gastric segments according to lesion size and histological analysis

	Procedure time, distal stomach (n = 99) (minutes)	Procedure time, proximal stomach (n = 49) (minutes)	P value
Neoplasm size
< 30 mm	83.04 ± 37.55	108.65 ± 44.58	< 0.001
≥ 30 mm	111.90 ± 44.00	154.76 ± 72.34	< 0.001
Histological type of resected specimen
Benign neoplasms	90.88 ± 37.07	111.66 ± 44.47	0.002
Low grade dysplasia	78.38 ± 24.30	96.87 ± 19.19	< 0.001
High grade dysplasia	92.72 ± 36.82	158 ± 78.07	< 0.001
Adenocarcinoma	112.62 ± 50.95	136.05 ± 67.44	0.017

Table 3 Comparison of neoplastic invasion in depth between both gastric segments, n (%)

	Distal stomach	Proximal stomach	P value
Adenocarcinoma
Intramucosal	33.3 (33/99)	20.4 (10/49)	0.052
Submucosal invasion	4.0 (4/99)	14.2 (7/49)	0.013
SM1 invasion	25 (1)	28.5 (2)	0.106
SM2 invasion	75 (3)	71.4 (5)	0.035

SM: Submucosal.

Table 4 Gastric endoscopic submucosal dissection learning curve analysis for distal stomach, n (%)

	Phase I (n = 33)	Phase II (n = 33)	Phase III (n = 33)	P value
En bloc resection	33 (100)	33 (100)	31 (93.9)	0.540
Complete resection (R0)	30 (90.9)	33 (100)	30 (90.9)	1.0
Curative resection	28 (84.8)	33 (100)	29 (87.8)	1.0
Size (mean), mm	26.4 (10-60)	29.8 (15-60)	24.7 (10-60)	0.495
Procedure time, mean ± SD, minutes	98.2 ± 49.9	94.0 ± 38.4	99.0 ± 40.4	0.863
Adverse events
Overall adverse event rate	0	2 (6.0)	3 (9.0)	0.296
Digestive bleeding	0	2 (6.0)	2 (6.0)	0.540
Perforation	0	0	1 (3.0)	0.540
Histological type of lesions
Benign neoplasms	7 (21.2)	6 (18.1)	6 (18.1)	0.540
Low grade dysplasia	3 (9.0)	6 (18.1)	10 (30.3)	0.296
High grade dysplasia	8 (24.2)	9 (27.2)	7 (21.2)	1
Adenocarcinoma (according to depth of tumor invasion)
Intramucosal	13 (39.3)	12 (36.3)	8 (24.2)	0.296
SM1 invasion	0	0	1 (3.0)	0.540
SM2 invasion	2 (6.0)	0	1 (3.0)	1

SM: Submucosal.

Table 5 Gastric endoscopic submucosal dissection learning curve analysis for proximal stomach, n (%)

	Phase I (16 cases)	Phase II (16 cases)	Phase III (17 cases)	P value
En bloc resection	15 (93.7)	14 (87.5)	13 (76.4)	0.296
Complete resection (R0)	14 (87.5)	11 (68.7)	11 (64.7)	0.540
Curative resection	12 (75.0)	10 (62.5)	10 (58.8)	0.540
Size (mean), mm	17.2 (10-35)	28.6 (15-40)	32.7 (12-80)	0.035
Procedure time, mean ± SD, minutes	110.3 ± 52.8	126.2 ± 63.6	145.0 ± 67.2	0.348
Adverse events
Overall adverse event rate	0	0	5.8 (1/17)	0.540
Digestive bleeding	0	0	5.8 (1/17)	0.540
Perforation	0	0	0	1
Histological type of lesions
Benign neoplasms	6 (37.5)	5 (31.2)	0	0.296
Low grade dysplasia	2 (12.5)	2 (12.5)	4 (23.5)	0.540
High grade dysplasia	1 (6.2)	2 (12.5)	9 (52.9)	0.296
Adenocarcinoma (according to depth of tumor invasion)
Intramucosal	3 (18.7)	5 (31.2)	2 (11.7)	1
SM1 invasion	1 (6.2)	0	1 (5.8)	1
SM2 invasion	3 (18.7)	2 (12.5)	1 (5.8)	0.296

SM: Submucosal.

Table 6 Comparative table of world-wide outcomes in gastric endoscopic submucosal dissection in proximal stomach

Ref.	En bloc resection rate	Complete resection rate	Curative resection rate	Adverse events rate	Procedure time, mean ± SD (minutes)	Submucosal neoplastic invasion
Current study	85.7 (42/49)	73.4 (36/49)	65.3 (32/49)	2.0 (1/49)	129.08 ± 63.91	14.2 (7/49)
Cho et al[28], 2023	100 (12/12)	91.7 (11/12)	83.3 (10/12)	16.7 (2/12)	Not specified	Not specified
Kim et al[13], 2017	92.0 (46/50)	88.0 (44/50)	94.1 (16/17)	4.0 (2/50)	33 ± 18	17.6 (3/17)
Kang et al[27], 2017	92.5 (62/67)	94.0 (63/67)	Not specified	Not specified	Not specified	22.9 (20/67)
Yoon et al[14], 2014	84.7 (83/98)	80.6 (79/98)	Not specified	13.3 (13/98)	90.51 ± 58.06	Not specified