What are blood tests for cancer?
Blood tests for cancer are diagnostic tools that help detect the presence of cancer, monitor its progression, or evaluate treatment effectiveness. These tests analyze substances in the blood, such as proteins, cells, or chemicals, that may indicate the presence of cancer.
In most cases, you’ll need more than blood tests for an official diagnosis, but a blood test can help detect some blood cancers, such as:
- Hodgkin lymphoma
- Non-Hodgkin lymphoma
- Leukemia
- Multiple myeloma
What are the different types of blood tests?
There are four main types of cancer blood tests:
Complete Blood Count (CBC)
A CBC measures the number and types of blood cells in your blood. This test may reveal abnormalities, such as an unusually high or low white blood cell count, which can indicate blood cancers like leukemia or lymphoma.
Tumor Marker Tests
A tumor marker test detects substances that certain types of cancer cells release into the blood. High levels of these chemicals in the blood can be a sign of cancer:
- PSA – may indicate prostate cancer.
- CA-125 – often associated with ovarian cancer.
- CEA – linked to colorectal and other cancers.
- AFP – can indicate liver or germ cell tumors.
Blood Protein Tests
A blood protein test analyzes proteins in the blood to detect abnormalities. High protein levels could indicate certain types of cancers. Some tests, like the electrophoresis test, can identify abnormal antibodies in the blood which may indicate multiple myeloma.
Circulating Tumor Cell Tests (CTC)
A CTC is a form of liquid biopsy that checks your blood for cancer. It detects tiny pieces of tumors that have broken off and are circulating your blood stream. A CTC is useful for monitoring metastatic cancers like breast, colorectal, or prostate cancer.