Increasing prevalence of advanced colonic polyps in young patients undergoing colonoscopy in a referral academic hospital in Hong Kong

Table 1 Histology of polyps n (%)

	No. of polyps	No. of advanced polyps	No. of patients	No. of patients with advanced polyps
	(n = 1856)	(n = 613)	(n = 880)	(n = 376)
Villous component	196 (10.5)	196 (31.9)	148 (18.8)	148 (39.3)
Villous	34 (1.8)	34 (5.5)	23 (2.6)	23 (6.1)
Tubulovillous	162 (8.7)	162 (26.4)	125 (14.2)	125 (33.2)
Tubular	1014 (54.6)	416 (67.9)	485 (55.1)	227 (60.4)
Flat adenoma	5 (0.3)	1 (0.2)	2 (0.2)	1 (0.3)
Serrated adenoma	6 (0.3)		3 (0.3)
Hyperplastic	339 (18.3)		131 (14.9)
Other	296 (16.0)		111 (12.6)

Table 2 Prevalence of advanced polyps by location n (%)

	Period I1998-2001	Period II2002-2005	Total
	(n = 237)	(n = 376)	(n = 613)
Location
Right	46 (19.4)	91 (24.2)	137 (22.3)
Left	115 (48.5)	130 (34.6)	245 (40.0)
Both	76 (32.1)	155 (41.2)	231 (37.7)

Table 3 Characteristics of advanced polyps n (%)

	Period I	Period II	Total	P-value
	1998-2001	2002-2005
Gender
Male	139 (58.6)	244 (64.9)	383 (62.5)
Female	98 (41.4)	132 (35.1)	230 (37.5)	P > 0.05
Age (yr)
≤ 60	42 (17.7)	99 (26.3)	141 (23.0)
> 60	195 (82.3)	277 (73.7)	472 (77.0)	P < 0.05
Location
Right	85 (35.9)	163 (43.4)	248 (40.5)
Left	152 (64.1)	213 (56.6)	365 (59.5)	P > 0.05
Tubulovillous
Yes	51 (21.5)	111 (29.5)	162 (26.4)
No	186 (78.5)	265 (70.5)	451 (73.6)	P < 0.05

Table 4 Polyps with screening as indication n (%)

	Period I	Period II	Total no of CRCs	P-value
	1998-2001	2002-2005
	(n = 183)	(n = 606)	(n = 789)
Advanced
Yes	43 (23.5)	190 (31.4)	233 (29.5)
No	140 (76.5)	416 (68.6)	556 (70.5)	P < 0.05

Table 5 Prevalence of cancer in male subjects by age n (%)

	Period I	Period II	Total no of CRCs	P-value
	1998-2001	2002-2005
	(n = 82)	(n = 91)	(n = 173)
Age (yr)
≤ 60	19 (23.2)	15 (16.5)	34 (19.7)
> 60	63 (76.8)	76 (83.5)	139 (80.3)	P > 0.05