Prospective evaluation of fecal calprotectin as a screening biomarker for colorectal neoplasia.

Murine fecal proteomics: a model system for the detection of potential biomarkers for colorectal cancer.

Background:

Mass screening for colorectal cancer reduces mortality and, with recent advances in molecular genetics, molecular stool-based tests have produced promising results. This article reviews this innovation and discusses its clinical significance.



Methods:

Medline searches were used to identify recent key articles relating to stool-based testing. Further articles were obtained by manual scanning of the reference lists of identified papers.



Results:

Current screening methods are based on endoscopic, radiological and stool-based testing. Recent recognition of the adenoma–carcinoma sequence and pathophysiological studies of colonic epithelium have enabled tumour markers to be used in the screening setting. Non-invasive molecular stool testing has now been shown to have a high sensitivity and specificity.



Conclusion:

Recent studies on molecular stool-based testing have shown higher sensitivity and specificity than earlier studies, but larger clinical trials are required. Laboratory methods are still undergoing research, with the aim of improving sensitivity to allow large-scale testing. Copyright © 2004 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

Molecular stool screening for colorectal cancer

Two dogs were referred for investigation of lethargy and anaemia. Preliminary examinations by the referring veterinary surgeons had revealed severe anaemia, which was poorly regenerative. In one case, the anaemia was microcytic and, in the other, it was hypochromic. These findings were suggestive of chronic blood loss anaemia. Neither dog had external signs of gastrointestinal disease, although one had vomited on a single occasion during the two weeks preceding referral. Although both dogs were producing grossly normal faeces, further investigations detected faecal occult blood. Multiple full thickness gastrointestinal biopsies were taken at laparotomy. These showed segmental eosinophilic enteritis of the duodenum and proximal jejunum in one case, and marked chronic lymphocytic gastritis in the other. Both cases illustrate the fact that severe systemic disease can result from gastrointestinal pathology in the absence of clinical signs of gastrointestinal disease.

Two cases of severe iron-deficiency anaemia due to inflammatory bowel disease in the dog.

https://www.cghjournal.org/article/S1542-3565(07)00286-8/pdf

Detection of colorectal disease by stool defensin assay: an exploratory study.

Fecal α1-antitrypsin measurement may be of value for the detection of coloreactal neoplasia and is compared with the HemoQuant test in 119 subjects with either a screen-positive Hemoccult result (N=78) or iron-deficiency anaemia (N=41). Nineteen patients were found to have coloreactal cancer, 35 had colorectal adenomatous polyps, 5 had inflammatory bowel disease, and 60 had no detected cause of occult blood loss. Of the cancer patients, 63% (12/19) were detected by fecal α1-antitrypsin, and 63% (12/19) by HemoQuant. Of the adenomas >1 cm in diameter 33% (7/23) were detected by fecal α1-antitrypsin and 26% (6/23) by HemoQuant. There was a poor correlation between fecal α1-antitrypsin, and HemoQuant results for colorectal cancers (r=0.37,P>0.05), and combining the tests, the sensitivity for colorectal cancer was incerased to 84% (16/19). Fecal proteins loss, as measured using α1-antitrypsin, appears to involve largely different mechanisms from that of blood loss from colorectal cancers.

Julie Stanley

Papers

Fecal α1-antitrypsin detection of colorectal neoplasia : an evaluation using HemoQuant