Multicenter randomised controlled trial comparing the high definition white light endoscopy and the bright narrow band imaging for colon polyps

Table 1 Characteristics of patients and colonoscopy performance in both groups n (%)

Parameters	bNBI (n = 495)	WLE (n = 511)	P value
Patients
Men	210 (42.43)	237 (46.38)	0.207
Age, mean ± SD	58.31 ± 6.17	58.36 ± 6.13	0.904
BMI, mean ± SD	23.75 ± 3.29	23.74 ± 2.99	0.942
Current smoker	24 (4.9)	29 (5.7)	0.536
Current drinker	38 (7.7)	44 (8.7)	0.815
Current use of NSAID	6 (1.2)	9 (1.8)	0.705
Current use of aspirin	13 (2.6)	22 (4.3)	0.345
Current use of warfarin	0	2 (0.4)	0.232
Comorbidities
Hypertension	123 (24.8)	131 (25.6)	0.774
Diabetes	56 (11.3)	32 (6.3)	0.005
Ischemic heart disease	10 (2.0)	10 (2.0)	0.943
Chronic obstructive airway disease	2 (0.4)	0	0.15
Previous stroke	1 (0.2)	2 (0.4)	0.582
Cirrhosis	1 (0.2)	1 (0.2)	0.982
Gastro-esophageal reflux	10 (2)	8 (1.6)	0.587
Dyslipidemia	31 (6.3)	29 (5.7)	0.694
History of cancer	19 (3.8)	12 (2.3)	0.172
Examination time (min), mean ± SD
Time to cecum	6.66 ± 4.56	7.06 ± 4.94	0.183
Time for withdrawal	11.23 ± 6.36	9.84 ± 5.03	< 0.0001

bNBI: Bright narrow band imaging; WLE: White light endoscopy.

Table 2 Pathologic diagnosis in both bright narrow band imaging and high definition white light endoscopy n (%)

	bNBI (n = 495)	HD-WLE (n = 511)	P value
Adenomas	341	326	0.425
Subjects with adenomas2 (ADR)	185 (37.4)	201 (39.3)	0.523
Adenomas per adenoma carrier1	1.84	1.62	0.129
Size
Subjects with 0-5 mm adenomas2	149 (30.1)	162 (31.2)	0.583
Subjects with 6-9 mm adenomas2	52 (10.5)	52 (10.2)	0.864
Subjects with ≥ 10 mm adenomas2	31 (6.3)	31 (6.1)	0.897
Adenomas < 10 mm	306	290	0.283
Adenomas 0-5 mm	241	229	0.334
Adenomas 6-9 mm	65	61	0.896
Adenomas ≥ 10 mm	35	36	0.837
Location
Right-sided adenomas	157	155	0.400
Left-sided adenomas	168	159	0.797
Histopathology
Carcinomas	3	5	0.418
Tubular	315	304	0.343
Tubulovillious	10	12	0.689
Villious	2	0	NA
Adenomas with high grade dysplasia	6	7	0.992
Hyperplastic polyps	178	136	0.020
Hyperplastic polyps < 10 mm	176	135	0.020
SSA/Ps	13	7	0.257
Subjects with SSA/P, n (SSA/P-detection rate in %)	13 (2.6)	6 (1.2)	0.091
Inflammatory polyps	12	14	0.572
Indeterminate or non-significant	16	15	0.987
Not submitted for histologic examinations	13	31	0.010
Xanthoma	1	1	0.961

¹Mann-Whitney's U test used;

²χ² test or Fisher’s exact test used as appropriate. HD-WLE: High definition white light endoscopy; bNBI: Bright narrow band imaging.

Table 3 Polyp categorization according to Sano’s classification - Hyperplastic/SSA/P vs adenoma/cancer

	Pathology		Total
	Hyperplastic/ SSA/P	Adenoma/cancer
Sano’s classification
I	245	24	269
II, IIIa, IIIb	36	555	591
Total	281	579

Sensitivity of predicting adenoma = 95.7% (93.4% to 97.2%); Specificity of predicting adenoma = 86.5% (81.7% to 90.2%); PPV of predicting adenoma = 93.9% (91.7% to 95.6%); NPV of predicting adenoma = 91.0% (86.4% to 94.0%).

Table 4 Polyp characterisation according to Sano’s classification - Adenoma vs cancer

	Pathology		Total
	Adenoma	Cancer
Sano’s classification
II, IIIa	547	1	548
IIIb	0	7	7
Total	547	8

Sensitivity of predicting cancer = 87.5% (47.4% to 99.7%); Specificity of predicting cancer = 100% (99.3% to 100%); PPV of predicting cancer = 100% (59.0% to 100%); NPV of predicting cancer = 99.8% (98.7% to 100%).

Table 5 Polyp characterisation based on Sano’s classification for polyps in the rectosigmoid region (5 mm or less in size)

	Pathology		Total
	Hyperplastic	Adenoma/cancer
Sano’s classification
I	146	10	156
II, IIIa, IIIb	7	130	137
Total	153	140

Sensitivity of predicting adenoma = 94.5% (89.1% to 97.3%); Specificity of predicting adenoma = 95.4% (90.6% to 97.8%); PPV of predicting adenoma = 94.8% (89.5% to 97.5%); NPV of predicting adenoma = 93.7% (87.7% to 96.9%).