Researchers are studying new blood markers to detect colorectal cancer early. For example, tumors release into the blood small fragments of RNA called microRNAs packaged into tiny sac-like structures called exosomes. Exosome-packaged microRNAs he shown promise for early detection of pancreatic cancer and may also be useful for early detection of colorectal cancer (10, 11).
Another approach being tested is whether artificial intelligence (AI)–based technology called computer-aided detection (CAD) can improve the interpretation of colonoscopy imaging by experienced doctors. Several clinical trials he found that the addition of CAD increased the detection of small polyps that are unlikely to become cancer but not of advanced adenomas. However, these studies used relatively primitive AI-based CADs. Newer AI technologies may improve the detection of advanced adenomas by CAD.
Researchers are continuing to improve the sensitivity of stool-based screening for detecting advanced adenomatous polyps, which can potentially become colorectal cancer, by testing for the presence of other (non-DNA) types of biomarkers. For example, a multitarget stool RNA (mt-sRNA) test (ColoSense) that detects occult hemoglobin (with FIT), along with levels of eight colorectal cancer–associated RNA markers was approved in 2024 for colorectal cancer screening. (This test is not yet commercially ailable, and experts he not yet recommended a screening interval for it.)
Researchers he also found that measuring three protein biomarkers in stool—hemoglobin, calprotectin, and serpin family F member 2—improved the ability of FIT to detect advanced lesions (including colorectal cancer) without reducing its specificity (12).
Capsule colonoscopy (also called capsule endoscopy) is a technique that continues to be explored to improve visualization of the colon. A person swallows a pill-like capsule that contains a tiny wireless camera. The camera takes pictures of the inside of the digestive tract and sends them to a small recorder that is worn on the patient’s waist or shoulder. The pictures are then viewed on a computer by the doctor to check for signs of disease. The capsule passes out of the body during a bowel movement. Cleansing of the colon is still necessary before this test. This method is currently approved for patients with an incomplete colonoscopy and for detection of colon polyps in patients with evidence of lower GI bleeding but not as a stand-alone screening test for people at erage risk.