Emerging role of colorectal mucus in gastroenterology diagnostics

Abstract

Colonoscopy is currently the gold standard for diagnosis of inflammatory bowel disease (IBD) and colorectal cancer (CRC). This has the obvious drawback of being invasive as well as carrying a small risk. The most widely used non-invasive approaches include the use of faecal calprotectin in the case of IBD and fecal immunochemical test in the case of CRC. However, the necessity of stool collection limits their acceptability for some patients. Over the recent years, there has been emerging data looking at the role of non-invasively obtained colorectal mucus as a screening and diagnostic tool in IBD and CRC. It has been shown that the mucus rich material obtained by self-sampling of anal surface following defecation, can be used to measure various biomarkers that can aid in diagnosis of these conditions.

Keywords: Colorectal cancer; Colorectal mucus; Crohn's disease; Faecal calprotectin; Inflammatory bowel disease; Ulcerative colitis.

Figure 1

Box and whisker plot and individual result distributions and receiver operating characteristic curve for the combined CALEDN test at stage 1 of the study. In the panel within the inflammatory bowel disease group, blue and red circles correspond to Crohn’s disease and ulcerative colitis cases, respectively. AUC: Area under the curve; IBS: Irritable bowel syndrome; CD: Crohn’s disease; UC: Ulcerative colitis. Citation: Loktionov A, Chhaya V, Bandaletova T, Poullis A. Inflammatory bowel disease detection and monitoring by measuring biomarkers in non-invasively collected colorectal mucus. J Gastroenterol Hepatol 2017; 32: 992-1002. Copyright© The Authors 2017. Published by John Wiley and Sons. A: Box and whisker plot; B: Receiver operating characteristic curve.

Figure 2

Receiver operating characteristic curves for ‘screening’ (blue) and ‘triage’ (red) settings for haemoglobin, C-reactive protein, tissue inhibitor of metalloproteinase 1, M2-pyruvate kinase, matrix metalloproteinase 9, peptidyl arginine deiminase-4, epidermal growth factor receptor, calprotectin and eosinophil-derived neurotoxin. A: Haemoglobin; B: CRP; C: TIMP1; D: M2-PK; E: MMP9; F: PADI4; G: EGFR; H: calprotectin; I: EDN. Citation: Loktionov A, Soubieres A, Bandaletova T, Francis N, Allison J, Sturt J, Mathur J, Poullis A. Biomarker measurement in non-invasively sampled colorectal mucus as a novel approach to colorectal cancer detection: screening and triage implications. Br J Cancer 2020; 123: 252-260. Copyright© The Authors 2020. Published by John Wiley and Sons.