You haven’t felt well in months. There is a gnawing pain in your belly. Most days you have a low-grade headache. You wake up in the middle of the night and can’t fall back asleep. You wake more tired than when you went to bed. Your gluten-free diet hasn’t made much difference. All the superfoods and supplements you take every day hardly helped. You can’t blame it on alcohol because you don’t drink. You’ve done detox programs, elimination dieting, and even water fasting, but still don’t feel right. Mindfulness meditation calms your anxiety a little.
But, the worry is still there in the back of your mind all the time: “Could I have cancer?”
Perhaps many of your family members have had cancer, and you want to know if you’re next.
Is there a blood test to tell if you have cancer?
Clues Found in Standard Tests
Standard clinical laboratory tests include blood counts, chemistry studies, and a lipid profile. They are not designed to detect cancer, but clues about some types of cancer do appear in some of these tests.
A complete blood count (CBC) looks at your red and white blood cells, and platelets. A persistently low number of white cells (WBCs) might mean leukemia or a weak immune system. In a comprehensive metabolic panel (CMP)a very high levels of alkaline phosphatase (ALK) could point to tumor activity.
But don’t count on standard blood tests to screen for cancer.
Clues Found in Tumor Markers
Tumor markers are useful in following current cancer therapy. However, they are not effective at determining if you have cancer. Conditions other than cancer can make tumor marker levels rise. And, they may not be raised in the early stages of cancer. Tumor markers are best as trackers when you already know you have cancer or to make sure you remain cancer free after treatments.
Common Tumor Markers:
- AFP (Alpha-fetoprotein) helps in the diagnosis of liver cancer.
- CA 15.3 and CA 21.29 tell if your breast cancer treatments are working.
- CA 19.9 provides clues about pancreas cancer, as well as cancer of the gallbladder and bile duct.
- CA 125 provides clues about ovarian cancer.
- CEA helps keep track of colorectal cancer.
- PSA – provides clues about prostate cancer.
Tumor markers are not approved as screening tests because they are not specific or sensitive enough. However, they provide clues about the possibility of having cancer and are very useful for evaluating the effectiveness of therapy. If the marker number goes down, you’re improving.
Certain gene mutations suggest a tendency to develop cancers that occur families. And, some genetic cancer markers as associated with specific cell lines. Others provide profiles for a variety of cancers.
Common Genetic Tests:
- BRCA1 and BRCA2 look at gene mutations associated with hereditary risk for breast, ovarian, and other cancers.
- MammaPrint 70 Gene Profile is a way of looking at your personal biology concerning early-stage breast cancer. It tells if you are at risk for a relapse or how aggressive your cancer might be.
- HER2 provides genetic clues about breast and stomach cancer and adenocarcinoma.
- EGFR is a gene mutation test associated with non-small cell lung cancer.
These genetic tests are FDA approved, which usually means they are covered by health insurance when ordered by a licensed doctor.
How Close Are We to Liquid Biopsies?
The Holy Grail of early cancer detection is a single test that screens someone’s blood for tell-tale signs of cancer. We’re not there yet, but Illumina with headquarters in San Diego is betting that the startup company Grail based in San Francisco will become the first to provide quick, accurate, and cost-effect cancer detection screen in a drop of blood.
It all started in the early 1980s at John Hopkins University with a research team led by Bert Vogelstein, MD. However, even then it was not a new concept. Scientists have known that tumors shed DNA into the blood since 1948. The latest versions of this concept would sequence the entire genome, picking up on DNA fragments from tumors.
Liquid biopsies can find cancer DNA before a tumor is seen on medical imaging like a CT scan. Several companies are at work on early cancer detection in a blood sample.
- GRAIL aims to detect cancer in healthy people. It scans for fragments of tumor DNA, which is an extraordinarily broad approach to identifying patterns in the blood that define cancer.
- AMSA or Anti-Maligin Antibody is a blood test developed by Oncolab in Boston. AMSA is elevated in nearly all types of cancer. It is highly accurate in predicting early-stage cancer and is normal in 96 percent of cases which no longer have cancer. It is precise for detection more than 90 percent of the time.
- TK-1 or Thymidine Kinase-1 is an enzyme found in living cells. TK-1 is responsible for DNA replication and repair. Cancer cells contain DNA and replicate explosively, releasing TK-1 into the blood stream. Testing for TK-1 helps to detect cancer in the early stages. Autoimmune disease, B12 deficiency, active infections, and recent surgery can affect TK-1 results.
Should You Get Screened for Cancer?
Since cancer is so prevalent in modern societies, it may be wise for everyone to get screened for cancer. The first generation of liquid biopsies is already available. They cost about $300. Better and more accurate tests will be available soon. Grail aims to get the costs to less than $100.
Remember, it takes a medical expert to determine if you have cancer. It requires a specialist to interpret all the sophisticated tests available to doctors. But for those body-hackers, the era of cancer screening is already here.