A study published on Wednesday showed that a blood test for colon cancer was effective, providing a new way to screen for a major contributor to cancer-related deaths.

The examination searches for genetic material released from cancerous cells and abnormal tissue growth. It is currently available for purchase in the United States at a cost of $895, but it has not yet been authorized by the Food and Drug Administration and is not typically covered by insurance providers. The manufacturer of the test, Guardant Health, expects to receive a decision from the FDA within this year.

The research showed that 83% of cancer cases were detected by the test, but it had a low success rate in identifying precancerous polyps compared to colonoscopy, which is considered the most effective method for colon cancer screening. In addition to detecting tumors, colonoscopies can potentially prevent the disease by removing polyps before they become cancerous.

However, there are individuals who opt out of taking the exam due to the inconvenience of taking time off work or the preparation required, which may include consuming a potent laxative to clear the bowels beforehand.

An easy option is a yearly stool examination, where individuals submit a stool specimen for laboratory evaluation.

According to Dr. Douglas Corley, the chief research officer for Kaiser Permanente, Northern California, the most effective test is the one that individuals are most likely to finish. He was not a part of the study. Offering people a selection boosts the number of individuals who will undergo screening.

In the United States, it is advised that adults between the ages of 45 and 75 who are at an average risk for colon cancer undergo screening. The frequency of screening varies depending on the chosen test, with a standard colonoscopy being recommended every ten years. While the number of individuals being screened is gradually increasing, it is still far from meeting the goal of 80% of eligible adults set by organizations such as the American Cancer Society.

Guardant suggests getting their Shield blood test every three years. Similar to a stool test, the blood test may require a colonoscopy follow-up if there is an abnormal outcome, resulting in additional expenses.

The research, funded by Guardant and documented in the New England Journal of Medicine, included 7,861 individuals in the United States who underwent both a colonoscopy and a blood test.

The blood test detected 83% of the colon cancers identified through colonoscopy, but it failed to detect 17%. This is in line with the accuracy of stool-based tests.

There were instances of inaccurate alerts as well: In 10% of cases where a colonoscopy did not detect any abnormalities, the blood test incorrectly suggested the possibility of colon cancer. This would lead to a significant number of individuals experiencing the stress and worry of additional colonoscopy examinations.

Corley stated that while the blood test is designed to detect the indicators of colon cancer, further research is necessary to determine if it could also identify other types of cancer and potentially produce inaccurate findings.

This year, it is projected that there will be over 153,000 new cases and 53,000 deaths from colorectal cancer in the United States, making it the second highest cause of cancer fatalities in the country and the third highest globally.

Dr. William Grady, one of the co-authors of the study and a member of Guardant’s scientific advisory board, stated that increased screening could potentially lead to a decrease in the number of deaths caused by cancer.

A different research, released on Wednesday in the same publication, showed that the updated version of the Cologuard stool test, which also detects DNA fragments, could potentially reduce the number of false alarms and subsequent colonoscopy procedures. This study, including over 20,000 participants, was funded by Exact Sciences, the manufacturer of the test.

According to Dr. Nabil Mansour of Baylor College of Medicine, having more options for our patients is beneficial. Although he was not involved in either study, he still plans on suggesting a colonoscopy for his patients. However, he is enthusiastic about the possibility of a reliable blood test becoming available.

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The Science and Educational Media Group of the Howard Hughes Medical Institute provides support for the Associated Press Health and Science Department. The AP is solely responsible for all of its content.