Risk factors for Mallory-Weiss Tear during endoscopic submucosal dissection of superficial esophageal neoplasms

Table 1 Clinicopathological features of all patients and lesions

Characteristics	n (%)/median (range)
No. of patients	337
Age in yr	62 (37-83)
Sex
Male	228 (67.7)
Female	109 (32.3)
Concomitant diseases
Atrophic gastritis	15 (4.4)
Hiatal hernia	2 (0.6)
History of distal gastrectomy	4 (1.2)
No. of lesions	373
Location
Upper	21 (5.6)
Middle	252 (67.6)
Lower	100 (26.8)
Longitudinal diameter of specimen in cm	4.0 (1.0-14.0)
Circumferential diameter of specimen in cm	2.5 (0.5-7.0)
Size of specimen in cm2	9.8 (0.5-70.0)
Circumferential extent of the mucosal defect
< 75%	268 (71.8)
≥ 75%	105 (28.2)
Histology and depth of invasion
Intraepithelial neoplasia	131 (35.1)
Mucosa	195 (52.3)
Sub-mucosa < 200 μm	21 (5.6)
Sub-mucosa ≥ 200 μm	26 (7.0)
Procedure time in min	60 (12-240)
En bloc resection	359 (96.2)
Curative resection	321 (86.1)
Type of ESD procedure
Conventional ESD	33 (8.8)
ESTD	340 (91.2)
Endoscopists
Experienced	224 (60.1)
Less-experienced	149 (39.9)
Adverse events
MWT	20 (5.4)
Perforation	6 (1.6)
Stenosis	46 (12.3)

ESD: Endoscopic submucosal dissection; MWT: Mallory-Weiss Tear; ESTD: Endoscopic submucosal tunnel dissection.