Can bowel cancer be detected in a blood test?

As a healthcare professional with expertise in medical diagnostics, I can provide you with information on the detection of bowel cancer through blood tests. While the faecal occult blood test (FOBT) is a common screening method for detecting microscopic amounts of blood in the stool, which can be indicative of conditions such as polyps, cancer, or other bowel disorders, it is not a blood test in the traditional sense. The FOBT does not diagnose cancer. Instead, if it detects blood, it serves as a preliminary indicator that further investigation is needed. In such cases, a doctor will typically recommend a colonoscopy, which is a more definitive diagnostic procedure, to be performed within 30 days. There are also blood tests that can be used to detect certain biomarkers associated with bowel cancer. These tests are not as common as FOBT for routine screening but may be used in certain circumstances. It's important to note that no single blood test is definitive for bowel cancer, and they are typically used in conjunction with other diagnostic methods. In summary, while blood tests can sometimes provide information that may suggest the presence of bowel cancer, the faecal occult blood test remains the primary non-invasive screening method for bowel conditions, including cancer.

The faecal occult blood test (FOBT) looks for microscopic traces of blood in your stools, which may be a sign of polyps, cancer or another bowel condition. An FOBT does not diagnose cancer, but if it finds blood, your doctor will recommend you have a colonoscopy (see below) within 30 days.