Less messy than a stool test and much easier than a colonoscopy, this blood test may help raise the number of people who choose to screen for this common cancer. — TNS
The US Food and Drug Administration (FDA) recently approved a new blood-based method of colon cancer detection, offering a new alternative to catch more cases of a leading cause of cancer deaths, but one some physicians caution is not without drawbacks.
The test, manufactured by American biotechnology company Guardant Health, uses a blood draw to test for colorectal cancer in adults aged 45 and older who have an average risk of colorectal cancer.
The test has been on the market for an USD895 (about RM3,993) out-of-pocket price, but US FDA approval is likely to expand access and insurance coverage (in the United States) of the option.
It is the first blood test approved by the agency as a primary screening option for the cancer, said the company in a press release, meaning that it may be a more accessible, non-invasive screening option for many patients not receiving regular screenings.
A study conducted in March (2024) found the test accurately caught 83% of colon cancer – similar to stool-based tests on the market – and found few precancerous growths.
The data suggests the test is not to be taken as a replacement for colonoscopies, some warn.
“This is a good alternative to the regular, gold standard screening test, which is colonoscopy,” said Brigham and Women’s Hospital Molecular Pathological Epidemiology programme chief Dr Shuji Ogino.
“The sensitivity, 83% – to me, it’s one in six patients, which may not be that great.
“But though we have to do colonoscopy screening – every one of us, in fact – in reality, not 100% of people are compliant with the guidelines.”
Colorectal cancer is the second leading cause of cancer deaths in the US, behind lung cancer, but is treatable if caught early.
US doctors recommend healthy adults ages 45 to 75 at average risk for colon cancer receive regular screenings.
Gastroenterology studies found that as many as three out of four patients who died of colon cancer were not up to date on screenings.
The rate of colorectal screening in the US is only about 60%, according to the American Cancer Society, well below the National Colorectal Cancer Roundtable goal of 80%.
“The persistent gap in colorectal cancer screening rates shows that the existing screening options do not appeal to millions of people,” Massachusetts General Hospital gastroenterologist and Harvard Medical School professor Dr Daniel Chung said in the Guardant Health release, calling the test a “compelling new solution to close this gap”.
Guardant Health co-CEO AmirAli Talasaz said the company will “launch this test in the near future”.
Dr Ogino noted the “black box” nature of the testing – guarded by the company’s patent process and unchecked by outside physicians – may be cause for caution.
However, the blood and stool test options provide important new, more inexpensive, easily done options for “interval screenings” between colonoscopies, he added, and may also be important to combat rising cases of colorectal cancer in patients under 50 years old.
“With the tests, like the stool tests, blood tests, colonoscopies, I think we can design the best way to offer a patient, a person of 40 years – and 45, and even 35-something – ways to detect cancer early enough,” he said.
“It’s a good thing.” – By Grace Zokovitch/Boston Herald/Tribune News Service