Cancer develops from normal cells within the body that accumulate genetic mutations, allowing the cells to proliferate uncontrollably, evade cell death, and give rise to unlimited numbers of cells. There are a number of forms of cancer, which differ in their cell of origin, and the aggressiveness and invasiveness of the tumor. Cancer detection relies on a number of medical tests, from body imaging like X-rays to biochemical blood tests.
CEA Testing
One blood test that can be used as a diagnostic tool for cancer is CEA testing. CEA stands for carcinogenic embryonic antigen, an antigen found in cancer cells. During cancer development, growth of some types of cancer cells leads to the increased secretion of CEA into the blood. A CEA test assesses the levels of CEA in the blood, with high levels of CEA indicating the presence of cancer. According to the BC Cancer Agency, CEA testing is primarily used to help test for and monitor colorectal cancer. Patients may receive regular CEA testing throughout cancer therapy, since a decrease in CEA levels can indicate successful cancer treatment, and sustained low levels after treatment can indicate a lack of cancer recurrence.
Onko-Sure
Another type of cancer blood test is Onko-Sure, which can detect a number of different cancers. According to Radient Pharmaceuticals, the test's developer, the Onko-Sure blood test can detect the presence of 14 types of cancer. This test is especially useful in testing for cancers that do not secrete other cancer markers, such as CEA. As a result, an Onko-Sure test can help identify cancers that other blood tests may miss. The test indicates the presence of protein fragments called FDPs, which occur when cancer cells break down their surroundings to facilitate more cancer growth. The Onko-Sure test checks for the presence of several FDPs and, therefore, acts as a sensitive test for several forms of cancer, reports Radient Pharmaceuticals.
CBC Test
A complete blood count test, or CBC test, can also aid in cancer diagnosis, according to MayoClinic.com. During a CBC test, the doctor collects a sample of blood, and tests for the cell composition for the blood sample. A CDC test can indicate the presence of abnormal cells that might occur in a blood related cancer. The test may also help diagnose metastatic cancers, since cancer cells often travel throughout the body in the bloodstream and may be detected in a blood sample. Although a CDC test can indicate the presence of cancer, doctors must perform additional testing to learn the origin and characteristics of the cancer.
