More people may be checked for colorectal cancer as a result of the new test, particularly adults who are too young for regular colonoscopies.
The Shield blood test from Guardant Health was authorized by the Food and Drug Administration on Monday in order to screen for colon cancer. Although the test is not intended to take the place of colonoscopies, physicians are becoming excited about it because they believe it might increase the alarmingly low number of screenings for the second-leading cause of cancer-related deaths in the US.
In the past, clinicians could use Shield as a screening tool for $895 out of their own pockets. With the FDA’s clearance, patients will have more access to the blood test since Medicare and commercial insurance companies are far more likely to pay for it.
An associate professor in the University of Texas MD Anderson Cancer Center’s gastrointestinal and medical oncology department, Dr. Arvind Dasari, referred to the clearance as a “welcome development.”
However, he issued a warning: “We’ll have to wait and see what the impact is going to be in terms of better screening and lower mortality rates.”
According to the American Cancer Society’s projections, colorectal cancer will claim the lives of almost 53,000 people this year.
According to research released in March, Shield had an 83% detection rate for colorectal malignancies. It functions by identifying the DNA released into the circulation by malignant tumors.
Later-stage malignancies, when tumors release more of the DNA, are the ones for whom it works best. According to the study, Shield only spotted 13% of polyps in an earlier stage.
The test would have to be administered, beginning at age 45, which is also the age at which colorectal screening is advised, at least every three years.
Not every positive test results in a diagnosis. Patients would still require a colonoscopy if the results showed cancer was present, so that medical professionals could determine the location and extent of tumor growth.
According to Robert Smith, senior vice president of Early Cancer Detection Science at the American Cancer Society, “people have to understand that a positive Shield test requires a colonoscopy to confirm that you have an advanced lesion or colorectal cancer, or that the results were false.” “If this test is positive and you haven’t undergone a colonoscopy, it’s not complete.”
Following the approval of Epigenomics’ Epi proColon in 2016, this is the second blood test used to screen for colon cancer. Smith said that due of doubts regarding its correctness, it is rarely employed. Neither Medicare nor private insurance will pay it either.
Colon cancer rates among those under 55 have been alarmingly rising since the mid-1990s, rising by 1% to 2% annually in that age range. The American Cancer Society reports that at the same time, cases and fatalities among persons 60 and older have been decreasing.
Seattle’s Fred Hutchinson Cancer Center gastroenterologist Dr. William Grady remarked, “What breaks my heart is that it’s preventable.” Getting to remove polyps during a colonoscopy that may have developed into cancer if left unchecked is one of my greatest delights.
In fact, colonoscopy is by far the most reliable method of detecting colorectal cancer—it is one of the few malignancies that may be avoided with screening. However, screening rates are really low. Less than 60% of eligible individuals have undergone the suggested screening.
“Currently, the largest issue with colon cancer is that a large portion of the population is not being screened,” stated Dr. Sapna Syngal, who is the director of strategic planning for early cancer diagnosis and prevention at the Dana-Farber Cancer Center in Boston. “This test is likely to have a tremendous impact if it raises the number of individuals getting screened.”
According to Grady, the leader of the Shield test research conducted in March, persons in their 40s and 50s are frequently the least inclined to comply with screening.
He stated, “These are folks who work, and a lot of them have kids. You have all these other duties in life that come in the way of taking care of yourself.
Colonoscopies require a lot of time, therefore patients must miss at least one day of work. There’s also a certain “ick” aspect that turns off a lot of folks. A small camera is inserted into the rectum by the doctors during the surgery to search for tumors or potential malignant regions.
The colon must be clearly visible to that camera. Patients must take a high dosage of laxatives the day before the colonoscopy. In other words, they use the restroom a lot.
The preparation for a colonoscopy is what most individuals find most unpleasant about the procedure, according to Electra Paskett, deputy director for population sciences and community engagement at the Ohio State University Comprehensive Cancer Center. “I believe that for many people, a blood test would be ideal.”
Fecal occult blood tests are another form of screening for colon cancer. These tests look for blood in the stool, which may indicate the presence of cancerous or precarious colon polyps. Precancerous polyps are harder to find with FIT-DNA tests like Cologuard, but they are more successful in identifying cancer.
For years, Newport Beach, California resident John Gormly, 77, has eschewed colonoscopy screening. He chose to take the Shield blood test when his doctor offered it to him.
“I don’t like the results at all,” he stated over the phone a few days later. I’m going to arrange for a colonoscopy for you. Gormly remembered. “I had stage 2 colon cancer, it turns out.” The tumor was entirely removed by the surgeons.
Gormly remarked, “Thank God I had taken that blood test.” “I never experienced any emotions and was unaware of any issues.” I don’t know how things would have worked out if not for the blood test.”
