Colorectal cancer is the third most diagnosed cancer in the U.S., and the debut of a new blood test could mean more Americans will get screened for it.
“Over 50 million eligible Americans do not get recommended screenings for colorectal cancer, partly because current screening methods are inconvenient or unpleasant,” said AmirAli Talasaz, co-CEO of Guardant Health. This week, the company and researchers released data about the new test.
Named the “Shield” test, it detects colorectal cancer signals in the bloodstream. These signals are from DNA that is shed by colorectal tumors, called circulating tumor DNA or ctDNA.
According to a study published Thursday in the New England Journal of Medicine, the Shield test is 83% sensitivity for colorectal cancer, 90% specificity for advanced neoplasia, and 13% sensitivity for advanced precancerous lesions in an average risk population. Data from a cohort of nearly 8,000 evaluable people were included in published research, which is part of the ECLIPSE study.
“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 William M. Grady, MD, a gastroenterologist at Fred Hutchinson Cancer Center. “The test, which has an accuracy rate for colon cancer detection similar to stool tests used for early detection of cancer, could offer an alternative for patients who may otherwise decline current screening options.”
Last summer, Exact Sciences conducted a poll to find reasons why 45-year-olds (the starting age for routine screening) avoid getting screened. Some of the top answers were: lack of time, lack of awareness regarding colorectal cancer risk, fear and stigma and lack of health insurance.
According to Audacy station KYW, an estimated 150,000 people were diagnosed with colon cancer last year, and several recent studies have found that a growing number of cases are occurring in people under the age of 50. WBBM also reported this week on an increase in cancer diagnoses among Americans before they turn 50.
Authors of the Shield test study said that while colorectal is one of the most common cancers, and the second leading cause of cancer deaths in the U.S., deaths related to the disease are 90% preventable with early detection.
“Publication of ECLIPSE follows Guardant Health’s submission of its premarket approval (PMA) application to the U. S. Food and Drug Administration (FDA) for Shield, which included key data points from the study,” said Guardant in a Wednesday press release.