Table 1.

Average sCD26 concentration for the groups studied according to the colonoscopy result.

No colorectal pathology	Clinical condition	n	Mean ± SD sCD26 (ng/mL)
	Rectal bleeding	8	651.5 ± 190.2
	Abdominal pain	10	586.1 ± 194.4
	Diarrhoea	9	649.5 ± 306.8
				641.2 ± 241.2
	Anaemia	7	370.8 ± 144.7
	Constipation	4	782.7 ± 194.6
	No symptoms*	30	698.5 ± 234.2
Colorectal pathology	Diagnosis	n	Mean ± SD sCD26 (ng/mL)
Non-inflammatory	Haemorrhoids	36	655.3 ± 240.4
bowel disease				612.2 ± 231.0
(non-IBD)	Diverticula	28	556.7 ± 209.6
Inflammatory	Colitis	20	413.2 ± 195.5
bowel disease				434.4 ± 239.7
(IBD)	Crohn's disease	6	505.1 ± 355.8
	Hyperplastic polyps	18	560.4 ± 201.3
Polyps	Non-advanced adenomas	40	611.1 ± 263.8	588.0 ± 246.5
	Advanced adenomas	48	566.7 ± 225.8
	Duke's A	2	513.9 ± 240.4
	Duke's B	12	369.8 ± 147.4
CRC				403.7 ± 278.2
	Duke's C	15	402.0 ± 360.3
	Duke's D	4	457.0 ± 323.0

SD: standard deviation of the mean; *: personal history of polyps or CRC, or familial history of CRC.