Breast cancer is a prevalent and potentially fatal disease. It can develop from any of the cell types that make up the breast, and develop into a tumor that can travel throughout the body, in a process called metastasis. The National Cancer Institute reports that breast cancer led to more than 192,000 new cancer diagnoses and more than 40,000 deaths in the United States in 2009.
CEA Testing
One blood test used to indicate the presence of breast cancer is the CEA test. CEA stands for carcinoembryonic antigen, a protein produced in some cancer cells found in normal adult tissue. CEA from cancer cells is released into the bloodstream, so analyzing the levels of CEA found in the blood can be used to indicate breast cancer.
A test indicating high CEA levels on its own is not sufficient to diagnose breast cancer. CEA is produced by a number of cancer types, and some lifestyle factors such as smoking can increase CEA levels. The CEA test may be used to complement other breast cancer tests to confirm diagnosis. CEA testing during breast cancer therapy can indicate resistant breast cancer cases if CEA levels remain high over the course of cancer therapy.
CA 15-3
CA 15-3 is another test that can indicate the presence of breast cancer. CA 15-3 stands for cancer antigen 15-3, a protein specifically found in breast cancer cells. CA 15-3 is produced by the cancer cells, so high levels of CA 15-3 in the blood indicate the presence of breast cancer. Lab Test Online UK indicates CA 15-3 can be used to indicate the presence of metastatic cancer, since early forms of breast cancer do not lead to significantly higher blood CA15-3 levels.
Like CEA testing, CA 15-3 blood testing allows doctors to gauge a patient's response to breast cancer therapy. A series of CA 15-3 tests that show decreasing levels of CA 15-3 indicate breast cancer remission, while sustained high levels indicate resistant breast cancer. CA 15-3 alone cannot be used as a diagnostic tool in breast cancer, but it can be used in combination with other tests to indicate breast cancer.
CellSearch System
A CellSearch blood test can be used to indicate the presence of metastatic breast cancer. During breast cancer metastasis, the tumor invades healthy surrounding tissue, and tumor cells circulate throughout the body to colonize in distant tissues. One way the cancer cells circulate throughout the body is in the blood. The CellSearch test measures the number of breast cancer cells in the blood, since the presence of tumor cells indicates metastatic breast cancer. CellSearch blood testing does not detect earlier-stage breast cancers that have not yet entered the bloodstream.
The CellSearch System is commonly used to indicate the efficacy of cancer therapy for metastatic breast cancer, reports EmaxHealth. Regular CellSearch blood testing after cancer remission can also be used to indicate breast cancer recurrence.
