A $5 Test Detects Colon Cancer Before Symptoms Appear

Researchers at the University of Exeter have found that their new colorectal cancer diagnostic test effectively catches the early signs of the disease. The easy-to-use, cost-effective fecal immunochemical test, or FIT, costs around $5 and alerts to the presence of trace amounts of blood within the stool. The study was recently featured in the British Journal of Cancer.

The study examined data from around 4,000 patients over the age of 50. Over the course of half a year, 618 of the participants had a positive FIT result. Only 43 of these had been diagnosed with colorectal cancer within the last year. 

Colorectal cancer is particularly difficult to diagnose because, during the early stages, patients may be asymptomatic. When symptoms such as stomach ache, anemia, or unexplained weight loss manifest, these can be attributed to other conditions, and as a result, the cancer is missed.

Colorectal cancer is the second leading cause of cancer-related death in the U.S. The vast majority of cases occur in individuals aged 50 or older. The cancer begins in the large intestine, the final segment of the digestive tract. It usually progresses from benign clumps of tissue on the inner surface of the colon, known as polyps, which can eventually become malignant.

Study author Joe Mays said the speed and accuracy of the test as evidenced from the data presented should provide physicians with the confidence to roll it out to their patients. Speaking on the impact of FIT, Mays said, “This led to a reduction in the expected rates of colonoscopy, and helped us build a business case for the ongoing commissioning of this service.”

On the next steps, Mays added: “Building confidence and familiarity with the test helped us to manage a crisis in endoscopy capacity caused by the COVID-19 pandemic. We're now keen to evidence the performance of the test in higher-risk populations."

According to Cancer Research UK’s head of early diagnosis, Jodie Moffatt, FIT’s highest value is in catching the disease within the subset of patients with low risk symptoms.

"FIT is already being used for people who don't have symptoms in the bowel screening program. So it's fascinating to see how this test may also be used in patients with low-risk symptoms to identify who needs further investigation,” said Moffatt.

“As with all tests, FIT isn't perfect and some cases can be missed so it's important that anyone whose symptoms persist, change, or worsen contact their GP, even if they've recently had a negative FIT result."

Sources: University of Exeter, British Journal of Cancer.