Early detection and treatment of colorectal adenomatous polyps and colorectal cancer is associated with decreased mortality for colorectal cancer.
However, accurate, non-invasive and compliant tests to screen for adenomatous polyps and early stages of colorectal cancer are not yet available.
A blood-based screening test is highly attractive due to limited invasiveness and high acceptance rate among patients.
Professor Rüegg and colleagues demonstrated whether gene expression signatures in the peripheral blood mononuclear cells were able to detect the presence of adenomatous polyps and early stages colorectal cancer.
|Colorectal cancer classifiers were able to detect colorectal cancer with a sensitivity of 78%|
|Alimentary Pharmacology & Therapeutics|
A total of 85 peripheral blood mononuclear cells samples derived from colonoscopy-verified subjects without lesion, with adenomatous polyps or with colorectal cancer were used as training sets.
A 42-gene panel for colorectal cancer and adenomatous polyps discrimination, including genes identified by Digital Gene Expression-tag profiling of PBMC, and genes previously characterized and reported in the literature, was validated on the training set by qPCR.
Logistic regression analysis followed by bootstrap validation determined colorectal cancer - and adenomatous polyps-specific classifiers, which discriminate patients with colorectal cancer and adenomatous polyps from controls.
The team observed that the colorectal cancer and adenomatous polyps classifiers were able to detect colorectal cancer with a sensitivity of 78%, and adenomatous polyps with a sensitivity of 46%, respectively.
Both classifiers had a specificity of 92% with very low false-positive detection when applied on subjects with inflammatory bowel disease or tumors other than colorectal cancer.
Professor Rüegg's team concludes, "This pilot study demonstrates the potential of developing a minimally invasive, accurate test to screen patients at average risk for colorectal cancer, based on gene expression analysis of peripheral blood mononuclear cells obtained from a simple blood sample."