Clinical features of post-colonoscopy colorectal cancer and real-world multi-scale correlation analysis

Table 1 Baseline characteristics, n (%)

Characteristic	Confirmed diagnosis	Non-PCCRC	PCCRC	P value
Sex				0.3551
Male	3306 (61.85)	20 (74.07)	26 (66.67)
Female	2039 (38.15)	7 (25.93)	13 (33.33)
Age				0.0081
< 60	2523 (47.20)	18 (66.67)	11 (28.21)
≥ 60	2822 (52.80)	9 (33.33)	28 (71.79)
Location				< 0.0012
Ileocecal region	130 (2.43)	1 (3.70)	4 (10.26)
Ascending colon	314 (5.87)	1 (3.70)	3 (7.69)
Hepatic flexure	125 (2.34)	1 (3.70)	0 (0.00)
Transverse colon	122 (2.28)	4 (14.81)	1 (2.56)
Splenic flexure	21 (0.39)	0 (0.00)	0 (0.00)
Descending colon	197 (3.69)	3 (11.11)	4 (10.26)
Sigmoid colon	1266 (23.69)	6 (22.22)	12 (30.77)
Rectum	3108 (58.15)	10 (37.04)	7 (17.95)
Anastomotic site	62 (1.16)	1 (3.70)	8 (20.51)
Sedation				0.0461
Present	3019 (56.48)	18 (66.67)	29 (74.36)
Absent	2326 (43.52)	9 (33.33)	10 (25.64)
Bowl preparation				0.0042
Excellent	590 (11.04)	0 (0.00)	1 (2.56)
Good	2118 (39.63)	14 (51.85)	15 (38.46)
Inadequate	927 (17.34)	11 (40.74)	9 (23.08)
Poor	1015 (18.99)	2 (7.41)	11 (28.21)
Unclear	695 (13.00)	0 (0.00)	3 (7.69)
Adenoma3				0.7741
Present	1264 (65.12)	15 (60.00)	12 (70.59)
Absent	677 (34.88)	10 (40.00)	5 (29.41)

¹Pearson’s χ² test.

²Simulated P value.

³n was calculated as the total number of endoscopic procedures performed (n = 5411), while n was calculated based on the number of unique patients (n = 2047).

PCCRC: Post-colonoscopy colorectal cancer.

Table 2 Clinical characteristics of post-colonoscopy colorectal cancer, n (%)

Characteristic	CRC surgery history		P value
	Absent (n = 23)	Present (n = 16)
Sex			0.1071
Male	13 (56.52)	13 (81.25)
Female	10 (43.48)	3 (18.75)
Age			0.7342
< 60	6 (26.09)	5 (31.25)
≥ 60	17 (73.91)	11 (68.75)
Reason			0.2602
Poor preparation	4 (17.39)	2 (12.50)
Exposure error	17 (73.91)	10 (62.50)
Biopsy error	2 (8.70)	1 (6.25)
Judgement error	0 (0.00)	3 (18.75)
Location			< 0.0012
Ileocecal region	1 (4.35)	3 (18.75)
Ascending colon	3 (13.04)	0 (0.00)
Transverse colon	1 (4.35)	0 (0.00)
Descending colon	2 (8.70)	2 (12.50)
Sigmoid colon	11 (47.83)	1 (6.25)
Rectum	5 (21.74)	1 (6.25)
Anastomotic site	0 (0.00)	9 (56.25)
Differentiation			0.1172
Well-differentiated	1 (4.35)	4 (25.00)
Moderately differentiated	15 (65.22)	6 (37.50)
Poorly differentiated	7 (30.43)	6 (37.50)
Missed diagnosis duration (month), mean ± SD	22 ± 10	16 ± 8	0.0393

¹Pearson’s χ² test.

²Fisher’s exact test.

³Welch two sample t-test.

CRC: Colorectal cancer.

Table 3 Multinomial regression analysis, post-colonoscopy colorectal cancer vs confirmed diagnosis and non-post-colonoscopy colorectal cancer

Outcome	Characteristic	n	Event n	OR	95%CI	P value
Non-PCCRC	Sex
	Female	2059	7	Reference	Reference	-
	Male	3352	20	1.47	0.49-4.47	0.493
	Age
	< 60	2552	18	Reference	Reference	-
	≥ 60	2859	9	0.22	0.08-0.64	0.006
	Location
	Sigmoid colon	1284	6	Reference	Reference	-
	Ileocecal region	135	1	0.41	0.04-4.67	0.471
	Ascending colon	318	1	0.61	0.05-7.40	0.696
	Hepatic flexure	126	1	2.97 × 109	1.01 × 109, 8.71 × 109	< 0.001
	Transverse colon	127	4	8.50	0.75, 96.48	0.084
	Splenic flexure	21	0	0.01	0.01-0.01	< 0.001
	Descending colon	204	3	1.62	0.26-9.92	0.603
	Rectum	3125	10	2.45	0.61-9.84	0.207
	Anastomotic site	71	1	0.31	0.03-3.25	0.327
	Sedation
	Absent	2345	9	Reference	Reference	-
	Present	3066	18	0.48	0.14-1.59	0.229
	Bowl preparation
	Good	2147	14	Reference	Reference	-
	Excellent	591	0	0.00	-	-
	Inadequate	947	11	1.06	0.33-3.41	0.917
	Poor	1028	2	0.21	0.04-1.17	0.075
	Unclear	698	0	0.00	0.00-0.00	< 0.001
Confirmed diagnosis	Sex
	Female	2059	2039	Reference	Reference	-
	Male	3352	3306	0.83	0.42-1.65	0.598
	Age
	< 60	2552	2523	Reference	Reference	-
	≥ 60	2859	2822	0.50	0.24-1.02	0.056
	Location
	Sigmoid colon	1284	1266	Reference	Reference	-
	Ileocecal region	135	130	0.31	0.10-1.01	0.052
	Ascending colon	318	314	1.10	0.30-4.04	0.880
	Hepatic flexure	126	125	1.95 × 109	6.64 × 108, 5.73 × 109	< 0.001
	Transverse colon	127	122	1.34	0.17-10.48	0.782
	Splenic flexure	21	21	1.19 × 109	1.19 × 105, 1.19 × 105	< 0.001
	Descending colon	204	197	0.50	0.16-1.57	0.232
	Rectum	3125	3108	3.64	1.42-9.36	0.007
	Anastomotic site	71	62	0.07	0.03-0.18	< 0.001
	Sedation
	Absent	2345	2326	Reference	Reference	-
	Present	3066	3019	0.64	0.29-1.41	0.269
	Bowl preparation
	Good	2147	2118	Reference	Reference	-
	Excellent	591	590	2.12	0.26-17.42	0.483
	Inadequate	947	927	0.63	0.27-1.47	0.286
	Poor	1028	1015	0.74	0.32-1.70	0.485
	Unclear	698	695	1.78	0.50-6.40	0.374

CI: Confidence interval; OR: Odds ratio; PCCRC: Post-colonoscopy colorectal cancer.

Table 4 Univariate and multivariate analyses of influencing factors among doctors (ordered logistic regression)

Characteristic	Univariable				Multivariable
	n	OR	95%CI	P value	n	OR	95%CI	P value
Withdrawal time (second)	29	0.99	0.97-1.01	0.224	29	0.98	0.95-1.00	0.045
Insertion time (second)	29	1.02	1.01-1.04	0.016	29	1.02	1.01-1.05	0.011
Standardized count of detected polyps (> 5 mm)	29	1.00	1.00-1.00	0.184	29	1.00	1.00-1.00	0.640
Picture	29	1.06	0.98-1.15	0.156	29	1.01	0.90-1.13	0.903

CI: Confidence interval; OR: Odds ratio.