May 24, 2024
Colon cancer

Breakthrough Blood Test for Colon Cancer Shows Promising Results in Study

A recent study has shown promising results for a blood test designed to detect colon cancer, offering a new method for screening a leading cause of cancer-related deaths. This blood test, which looks for DNA fragments shed by tumor cells and precancerous growths, performed well in the study, detecting 83% of cancers. The test is currently available for purchase in the U.S. for $895 but awaits approval from the Food and Drug Administration, with most insurers not covering it. Guardant Health, the maker of the test, is optimistic about receiving FDA approval later this year.

While colonoscopies remain the gold standard for colon cancer screening as they can detect precancerous growths and prevent the disease by removing them, many individuals are hesitant to undergo the procedure due to inconveniences such as time off work and the preparation involved. An alternative option to colonoscopies is an annual stool test, where individuals can send a stool sample to a lab for analysis.

Dr. Douglas Corley, the chief research officer for Kaiser Permanente, Northern California, emphasized the importance of offering various screening options to increase the number of individuals willing to get screened. In the U.S., screening is recommended for adults aged 45 to 75 at average risk for colon cancer, with the frequency depending on the chosen test.

Guardant Health recommends testing with its blood test called Shield every three years. This test, similar to a stool test, may require a follow-up colonoscopy for individuals with abnormal results, potentially leading to additional out-of-pocket costs. The study, sponsored by Guardant and published in the New England Journal of Medicine, included 7,861 participants who underwent both a colonoscopy and the blood test.

While the blood test detected 83% of cancers found through colonoscopy, it missed 17%, which is comparable to stool-based tests. However, the blood test also produced false alarms for 10% of individuals where no abnormalities were found during colonoscopy, causing unnecessary anxiety and potential follow-up procedures.

Dr. Corley emphasized the need for further research to determine the blood test’s effectiveness in detecting other types of cancer and potentially yielding misleading results. Colorectal cancer ranks as the second leading cause of cancer deaths in the U.S. and third globally, with over 153,000 new cases and 53,000 deaths expected in the U.S. this year.

A separate study published in the same journal showcased an updated version of the Cologuard stool test, which also looks for DNA fragments, showing improved performance in reducing false alarms. This enhancement may lead to fewer unnecessary follow-up colonoscopies for individuals undergoing the test. Dr. Nabil Mansour of Baylor College of Medicine expressed optimism about the availability of multiple screening options for patients, noting that despite continuing to recommend colonoscopies, the emergence of a reliable blood test is an exciting development for detecting colon cancer.

1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it