United States – An experimental blood test accurately diagnosed colon cancer in over 80 percent of those with the cancer confirmed through a clinical examination, researchers report.
Test Designed for Symptom
The test, which is meant for individuals that do not mind colonoscopies, is designed for symptom-free people with average risk.
“The results of the study are a promising step toward developing more convenient tools to detect colorectal cancer early while it is more easily treated,” said corresponding author Dr. William Grady, a gastroenterologist at Fred Hutchinson Cancer Center in Seattle, as reported by HealthDay.
As of right now, standards suggest beginning routine screening at age 45. However, according to Grady, only between 50% and 60% of those who are qualified for colon cancer screening actually get the tests done.
“Having a blood-based test for people to take during routine doctor’s visits could be an opportunity to help more people be screened,” he said in a Fred Hutchinson news release.
Multi-Site Clinical Trial Validates Test’s Accuracy
The blood test data was evaluated in a multi-site clinical trial conducted on individuals aged from 45 to 84. The number of participants exceeded 7,800 involved in the trial. The research received funding from a manufacturer of the Guardant Health Shield blood test.
The examination is based on testing colon cancer symptoms the gene gives as a result of tumor cells in one’s blood. In addition to the circulating tumor DNA or ctDNA, the new approaches are also employed to check for recurring cancer and there are some more tests for screening purposes.
Ultimately, 83% of participants whose cancer was verified through sequencing using genomic mutations of ctDNA tested positive. Seeing that seventeen percent were negative on blood tests is proof that colon cancer does not show on colonoscopy, did.
They observed that the test showed the highest sensitivity for colon cancers in their very early stages, and it is less sensitive for preexistent lesions that will take time to develop into cancers.
The results were published on March 14th in the New England Journal of Medicine.
Importance of Offering Screening Options
Grady compared the blood test’s sensitivity to that of stool-based tests, and he said it should ideally be higher than these ones or even the same. But he added that it is less costly than colonoscopy, which he believes is the most accurate colon cancer screening technology.
“Getting people to be screened for cancer works best when we offer them screening options and then let them choose what works best for them,” he said.
Colon Cancer in Younger Generations
In the U.S., colon cancer is the second major cause of cancer deaths in adults of all ages, as stated by the American Cancer Society. It is forecast that this year alone will add more than 53,000 deaths to this disease.
While the fatality rates among the elderly have declined, those in the younger generation are bound to the opposite trend. They have climbed roughly 1% every year since the 2000s, as reported by HealthDay.
“We continue to see younger people getting colorectal cancer, and it’s now the third most common cancer for people under the age of 50,” Grady said.