Chicken skin mucosa surrounding small colorectal cancer could be an endoscopic predictive marker of submucosal invasion

Table 1 Demographics of both groups [mean ± SD, n (%)]

		SM (37)	M (196)	P value
Age (mean ± SD, yr)		66.9 ± 9.6	61.24 ± 11.1	0.06
Sex	Male	25 (67.6)	110 (66.3)	0.879
	Female	12 (32.4)	56 (33.7)
Size (mm)		17.2 ± 4.1	13.4 ± 4.6	< 0.001
Location	Right colon	5 (13.5)	45 (23)	0.199
	Left colon	32 (86.5)	151 (77)

SM: Submucosal; M: Mucosal; SD: Standard deviation.

Table 2 Chicken skin mucosa prevalence in different morphological lesions, n (%)

		CSM (+) 73	CSM (-) 160	P value
M		51 (69.86)	145 (90.63)	< 0.001
SM		22 (30.14)	15 (9.37)
Morphology	Flat (IIa, LST)	11 (15.07)	50 (31.25)	0.007
	Pedunculated (Isp, Ip)	30 (41.1)	68 (42.5)
	Sessile (Is, Is + IIc)	32 (43.84)	42 (26.25)
Location	Left colon	66 (90.41)	117 (73.13)	0.03
	Right colon	7 (9.59)	43 (26.88)
Size	≥ 10 mm	65 (89.04)	124 (77.5)	0.037
	< 10 mm	8 (10.96)	36 (22.5)

CSM: Chicken skin mucosa; SM: Submucosal; M: Mucosal; LST: Laterally spreading tumor.

Table 3 Comparison of different morphological tumor types and depth of invasion in early colorectal cancer, n (%)

	Total	SM	M	P value
Morphology	233	37	196	0.252
Flat	61 (26.18)	12 (32.43)	49 (25)
Pedunculated	98 (42.06)	11 (29.73)	87 (44.39)
Sessile	74 (31.76)	14 (37.84)	60 (30.61)

SM: Submucosal; M: Mucosal.

Table 4 Comparison of morphological characteristics and invasion depth of early colorectal cancer under white light endoscopy, n (%)

Endoscopic finding	SM (37)	M (196)	P value
(All) CSM	22 (59.5)	51 (26.2)	< 0.001
(All) Ulceration or errhysis	10 (27.3)	8 (4.1)	< 0.001
(All) Demarcated depressed area	17 (46)	17 (8.7)	< 0.001
(All) Deeper red mucosal color	26 (70.3)	130 (66.3)	0.354
(P, S) Loss of lobulation	5/15 (33.3)	30/145 (20.7)	0.323
(P) Stalk swelling	6/11 (54.6)	12/87 (13.8)	0.04
(F) Fold convergency	2/49 (4.1)	4/12 (33.3)	0.11
(P, S) Fullness	28/147 (19)	8/25 (32)	0.14

CSM: Chicken skin mucosa; SM: Submucosal; M: Mucosal.

Table 5 Logistic regression analyses of the risk factors for invasion depth of early colorectal cancer under white light endoscopy

Variable	OR (95%CI)	P value
Size (≥ 10 mm/10 mm)	3.89 (1.35-11.26)	0.01
CSM (+/-)	2.54 (1.14-5.95)	0.04
Ulceration or errhysis (+/-)	5.44 (1.64-17)	0.006
Demarcated depressed area (+/-)	5.82 (2.31-14.6)	0.01
Stalk swelling	1.03 (0.26-4.06)	0.97

CSM: Chicken skin mucosa; OR: Odds ratio; CI: Confidence interval.

Table 6 Comparison of chicken skin mucosa prevalence and invasion depth in different lesion morphologies

	Total	SM	M	P value
Morphology	233	37	196	0.252
Flat	CSM (+)	5 (41.67)	6 (12.24)	0.03
	CSM (-)	7 (58.33)	43 (87.76)
Protruded	CSM (+)	7 (63.64)	23 (26.44)	0.03
	CSM (-)	4 (36.36)	64 (73.56)
Sessile	CSM (+)	10 (71.43)	22 (36.67)	0.02
	CSM (-)	4 (28.57)	38 (63.33)

CSM: Chicken skin mucosa; SM: Submucosal; M: Mucosal.

Table 7 Logistic regression analyses of risk factors for the occurrence of chicken skin mucosa

Variable	OR (95%CI)	P value
SM/M	3.76 (1.7-8.3)	0.01
Location (left/right colon)	2.45 (1.03-5.82)	0.04
Size (≥ 10 mm/< 10 mm)	1.15 (0.59-1.41)	0.09
Morphology (flat/pedunculated/sessile)	1.54 (0.79-3.06)
	1.66 (0.85-3.27)	0.03

CSM: Chicken skin mucosa; SM: Submucosal; M: Mucosal; OR: Odds ratio; CI: Confidence interval.