Tumor size discrepancy between endoscopic and pathological evaluations in colorectal endoscopic submucosal dissection

Table 1 Background characteristics and size assessment, n (%)

Item	Value
Background characteristics	n = 377
Lesion-related factors
Age in yr, mean	70
Sex
Male	231 (61)
Female	146 (39)
Location
Colon	298 (79)
Rectum	79 (21)
Morphology
Protruded	84 (22)
Flat	293 (78)
Histology
Adenoma	84 (22)
Adenocarcinoma	293 (78)
Localization
Over the haustra	212 (56)
On a flat lumen	165 (44)
Degree of circumference
≥ 1/3	40 (11)
< 1/3	337 (89)
Endoscopist-related factors
Experience
Experienced	186 (50)
Less-experienced	191 (50)
Hospital type
Referral hospital	351 (93)
Clinics	26 (7)
Size assessment
Endoscopic size in mm, mean ± SD	26.0 ± 10.5
Histological size in mm, mean ± SD	31.0 ± 15.2
Absolute percentage of the size discordance, mean ± SD	21.0 ± 15.4

Table 2 Univariate analysis of influential factors on incorrect scaling, n (%)

Item	Incorrect scaling group	Correct scaling group	P value
	n = 91	n = 286
Lesion-related factors
Pathological size in mm, mean	40	28	< 0.001
Location			0.750
Colon	73 (80)	225 (79)
Rectum	18 (20)	61 (21)
Morphology			0.210
Protruded	16 (18)	68 (24)
Flat	75 (82)	218 (76)
Histology			0.830
Adenoma	21 (23)	63 (22)
Adenocarcinoma	70 (77)	223 (78)
Localization			0.001
Over the haustra	65 (71)	147 (51)
On a flat lumen	26 (29)	139 (49)
Degree of circumference			< 0.001
≥ 1/3	21 (23)	19 (7)
< 1/3	70 (77)	267 (93)
Endoscopist-related factors
Experience			0.050
Experienced	37 (41)	150 (52)
Less-experienced	54 (59)	136 (48)
Hospital type			0.900
Referral hospital	85 (93)	266 (93)
Clinics	6 (7)	20 (7)

Table 3 Multivariate analysis of influential factors on incorrect scaling

Factor	Odds ratio	95%CI	P value
Pathological size	1.05	1.030-1.080	< 0.001
Location
Rectum	1.00
Colon	1.20	0.612-2.360	0.590
Localization
Over the haustra	1.00
On a flat lumen	1.56	0.877-2.750	0.130
Degree of circumference
< 1/3	1.00
≥ 1/3	1.09	0.414-2.870	0.860
Experience
Less-experienced	1.00
Experienced	0.44	0.259-0.760	0.003

95%CI: 95% confidence interval.

Table 4 Univariate analysis of influential factors on underscaling, n (%)

Item	Underscaling group	Correct scaling group	P value
	n = 75	n = 286
Lesion-related factors
Pathological size in mm, mean	44	28	< 0.001
Location			0.800
Colon	58 (77)	225 (79)
Rectum	17 (23)	61 (21)
Morphology			0.150
Protruded	12 (16)	68 (24)
Flat	63 (84)	218 (76)
Histology			0.400
Adenoma	20 (27)	63 (22)
Adenocarcinoma	55 (73)	223 (78)
Localization			0.001
Over the haustra	54 (72)	147 (51)
On a flat lumen	21 (28)	139 (49)
Degree of circumference			< 0.001
≥ 1/3	20 (27)	19 (7)
< 1/3	55 (73)	267 (93)
Endoscopist-related factor
Experience			0.056
Experienced	30 (40)	150 (52)
Less-experienced	45 (60)	136 (48)
Hospital type			0.760
Referral hospital	69 (92)	266 (93)
Clinics	6 (7)	20 (7)

Table 5 Multivariate analysis of influential factors on underscaling

Factor	Odds ratio	95%CI	P value
Pathological size	1.08	1.05-1.11	< 0.001
Location
Rectum	1.00
Colon	1.07	0.510-2.250	0.840
Localization
On a flat lumen	1.00
Over the haustra	1.36	0.705-2.600	0.340
Degree of circumference
< 1/3	1.00
≥ 1/3	0.65	0.227-1.890	0.290
Experience
Less-experienced	1.00
Experienced	0.36	0.192-0.666	0.001

95%CI: 95% confidence interval.

Table 6 Univariate analysis of influential factors on overscaling, n (%)

Factor	Overscaling group	Correct scaling group	P value
	n = 16	n = 286
Lesion-related factors
Pathological size in mm, mean	20	28	< 0.001
Location			0.210
Colon	15 (94)	225 (79)
Rectum	1 (6)	61 (21)
Morphology			1.000
Protruded	4 (25)	68 (24)
Flat	12 (75)	218 (76)
Histology			0.210
Adenoma	1 (6)	63 (22)
Adenocarcinoma	15 (94)	223 (78)
Localization			0.180
Over the haustra	11 (69)	147 (51)
On a flat lumen	5 (31)	139 (49)
Degree of circumference			1.000
≥ 1/3	1 (6)	19 (7)
< 1/3	15 (94)	267 (93)
Endoscopist-related factor
Experience			0.500
Experienced	7 (44)	150 (52)
Less-experienced	9 (56)	136 (48)
Hospital type			0.610
Referral hospital	16 (100)	266 (93)
Clinics	0 (0)	20 (7)

Table 7 Multivariate analysis of influential factors on overscaling

Factor	Odds ratio	95%CI	P value
Pathological size	0.86	0.779-0.945	0.002
Location
Rectum	1.00
Colon	3.67	0.464-29.000	0.220

95%CI: 95% confidence interval.