There are many types of tumor markers, some are specific to certain types of cancer, some are more general. There is no universal cancer marker which can screen for all types of cancer. It is best to discuss with your doctor or functional medicine advisor to determine the most appropriate tests for you.
Common types of conventional tumor markers are listed below:
- Alpha-fetoprotein (AFP) – liver cancer and germ cell tumors
- Beta-2-microglobulin – multiple myeloma, leukemia, and some lymphomas.
- CA125 – ovarian cancer
- CA19.9 – pancreatic, gallbladder, bile duct cancer.
- CA15.3 – breast cancer
These are just a few of the cancer markers most commonly used in conventional medicine. However, it should be noted that there are some limitations to the use of conventional markers. There can be both false negative and false positive results depending on the patient’s general health and the type of cancer to be identified. Some tumor markers may be high in some people who don’t have cancer and some markers may not increase or decrease appropriately when a cancer is developing or is in remission.
As with other laboratory tests, tumor markers must be both specific and sensitive, and the higher the sensitivity and specificity the more accurate the test will be. Cases where false positives can arise are where other medical conditions are present for example:
- AFP can be raised during pregnancy, liver disease, or inflammatory bowel disease (IBS)
- CA 15.3 can be raised during liver disease and with non-cancerous breast lesions.
- CA 19.9 can be raised during IBS, thyroid disease, pancreatitis.
- CEA can be raised from cigarette smoking, Hepatitis infection, pancreatitis peptic ulcer, cirrhosis, hypothyroidism.
So it’s vitally important to have your markers reviewed in accordance with your complete health history by a medical professional who can guide you appropriately.
False negatives can also occur when the test is not sensitive or specific enough at picking up a cancer developing in the body. For some specific cancers, like ovarian cancer, the CA 125 misses up to 20% of cases, so therefore we need more specific and reliable evaluations to help patients understand their potential risk.
There are alternative non-specific cancer markers which can provide an additional viewpoint of cancer risk in the body. American Metabolic Laboratories conducts a cancer markers test evaluating HCG (human chorionic gonadotrophin ) PHI enzyme (phosphohexose isomerase) and CEA. HCG is a hormone which is produced by cancer cells and is sensitive to 70% of all types of cancer. The laboratory evaluations of HCG are more sensitive than other tests because they measure both urine and blood levels. PHI is an enzyme of anaerobic activity in the body and has a sensitivity of up to 80% of all cancers. We know cancer is a development of cells in an anaerobic environment, that is growth without oxygen, so a systemic marker like PHI alongside HCG can be helpful in obtaining a more comprehensive evaluation of risk.
Another lab called RGCC based in Europe does a Circulating Tumor cells test. This involves a blood draw which is then centrifuged to isolate specific cancer cells in the blood. It’s a very sensitive test for cancers which have metastasized, as individual cancer cells splinter off from the main tumor site and migrate through the blood to other parts of the body. For cancers which are very localized or very early stage, the test may not pick them up.
Ultimately, deciding which test is most appropriate to consider depends on the patient, their current lifestyle and health history. Using a variety of cancer markers together with functional medicine evaluations we can determine risk more accurately than before. The further ‘upstream’ we can go to understanding the cellular dysfunction the better we can understand how to intervene with lifestyle measures which can help to keep cancer at bay.