New Blood Test May Catch Colorectal Cancer Before It Starts

Scientists are testing a new blood test that could help stop colorectal cancer before it ever develops. The test looks for dangerous growths in the colon called advanced adenomas, which are polyps that can turn into cancer if left alone. Researchers say removing these growths early can prevent cancer entirely. The findings were published in a major medical journal called The Lancet Gastroenterology & Hepatology.

The study tested the new blood test on more than 1,500 adults in China, Japan, and Spain. All of these adults were already getting a type of camera exam called a colonoscopy to check their colons. The blood test found 92% of colorectal cancers that were in early to middle stages, and it also spotted 81% of advanced adenomas. These are strong results for a simple blood draw.

Current blood tests that are already available can find colorectal cancer, but they are not very good at finding dangerous polyps that come before cancer. The new test is different because it can tell the difference between low-risk polyps, high-risk polyps, and actual cancer. This means doctors could use it to decide which patients need a colonoscopy right away and which ones can wait. It could also help identify people who may not need a colonoscopy at all.

Doctors still say that colonoscopies are the best way to screen for colorectal cancer. Blood tests and stool tests are usually suggested only for people who are unable or unwilling to get a colonoscopy. However, if someone gets a positive result on a blood test, they are more likely to follow up with a colonoscopy, earlier research has shown. That means the blood test could still save lives by getting more people to see their doctor.

The researchers noted that the blood test did have some limits. It was less accurate at finding flat areas in the colon that could be dangerous, known as sessile lesions. Scientists say larger studies with more people are needed before the test is ready for wide use. Even so, experts not involved in the study called it a promising step toward preventing cancer, not just finding it.

In a second health story, scientists warn that a common flavoring chemical found in e-cigarettes may harm developing babies. The chemical is called vanillin, and it is used to create vanilla flavor in many vaping products. Lab experiments showed that vanillin can damage human embryonic stem cells, which are the building blocks of a growing baby in the first weeks of pregnancy. These cells have the ability to grow into any type of cell in the body.

Researchers tested vanillin on these stem cells in test tubes because it would be wrong and dangerous to test the chemical on real pregnant women. They found that higher amounts of vanillin killed the cells outright. Lower amounts did not kill the cells but stopped them from being able to grow into different types of cells. Either outcome could seriously disrupt how a baby develops in the womb.

The scientists discovered that vanillin works by attaching to a protein on the surface of embryonic cells called TRPV4. When the researchers blocked that protein, the vanillin could no longer harm the cells. This finding helped explain exactly how the flavoring causes damage. The study was published in a journal called Human Reproduction.

Study leader Prue Talbot from the University of California, Riverside, said the results are a serious warning for women who vape. She pointed out that many women do not know which chemicals are in vaping products. The researchers said their findings may help explain why vaping has been linked to trouble getting pregnant and to miscarriages. Talbot urged doctors to tell pregnant patients, or those trying to become pregnant, to avoid vaping.