Table 1.

Baseline characteristics of patients with malignant colorectal obstruction.

Variable	Total	ND-GWI group	D-GWI group	p
	N = 509	N = 456	N = 53
Sex, n (%)				0.556
Male	288 (56.6)	256 (56.1)	32 (60.4)
Female	221 (43.4)	200 (43.9)	21 (39.6)
Age, mean (SD), years	62.3 ± 16.1	62.2 ± 16.2	63.7 ± 15.3	0.512
Emergency endoscopic SEMS, n (%)				0.457
Yes	96 (18.9)	84 (18.4)	12 (22.6)
No	413 (81.1)	372 (81.6)	41 (77.4)
Anesthesia endoscopic SEMS, n (%)				0.976
Yes	57 (11.2)	51 (11.2)	6 (11.3)
No	452 (88.8)	405 (88.8)	47 (88.7)
Degree of obstruction, n (%)				0.027
Total	426 (83.7)	376 (82.5)	50 (94.3)
Subtotal	83 (16.3)	80 (17.5)	3 (5.7)
Obstruction site, n (%)				0.038
Rectum	124 (24.4)	118 (25.9)	6 (11.3)
Sigmoid colon	202 (39.7)	168 (36.8)	28 (52.8)
Descending colon	85 (16.7)	78 (17.1)	7 (13.2)
Transverse colon	67 (13.2)	57 (12.5)	10 (18.9)
Ascending colon	37 (7.3)	35 (7.7)	2 (3.8)
Sharply angulated stricture, n (%)				<0.001
Presence	137(26.9)	102(22.4)	35(66.0)
Absence	372 (73.1)	354 (77.6)	18 (34.0)
Etiology, n (%)				0.356
Colorectal malignancy	468 (91.9)	421 (92.3)	47 (88.7)
Extracolonic malignancy	41 (8.1)	35 (7.7)	6 (11.3)
Carcinomatosis, n (%)				0.006
Presence	190 (37.3)	161 (35.3)	29 (54.7)
Absence	319 (62.7)	295 (64.7)	24 (45.3)
Organ metastasis				0.236
Presence	109 (21.4)	101 (22.1)	8 (15.1)
Absence	400 (78.6)	355 (77.9)	45 (84.9)
Experienced colonoscopist, n (%)				<0.001
Yes	313 (61.5)	301 (66.0)	12 (22.6)
No	196 (38.5)	155 (34.0)	41 (77.4)

ND-GWI group, non-difficult guidewire insertion group; D-GWI, difficult guidewire insertion group.

Experienced colonoscopists had placed self-expandable metal stents in more than 100 cases.