CA125 is a protein measured in the blood, often linked to ovarian cancer. Healthcare providers use this blood test as a tool to help manage individuals affected by the disease.
What is CA125
CA125, or cancer antigen 125, is a glycoprotein produced by certain cells. While often found on ovarian cancer cells, it can also be present on normal tissues. This protein is released into the bloodstream, where its levels are measured. Although sometimes called a “tumor marker,” elevated CA125 levels can also occur due to various non-cancerous conditions.
How CA125 is Used in Ovarian Cancer
The CA125 test has several applications in ovarian cancer management. One use is in monitoring treatment effectiveness, particularly chemotherapy. Periodic measurements help doctors observe if levels are decreasing, suggesting the therapy is working. Stable or rising levels may indicate the treatment is less effective or the disease is progressing.
The test also detects recurrence after initial ovarian cancer treatment. Regular CA125 tests help identify if the cancer has returned. A rise in levels after normalization post-treatment can be an early indicator of disease recurrence, prompting further investigation.
When ovarian cancer is suspected, especially with a pelvic mass, CA125 can aid diagnosis. It is used with other diagnostic methods, like imaging, to help differentiate between benign and malignant pelvic masses. An elevated CA125 level in a postmenopausal woman with a pelvic mass raises suspicion of ovarian cancer, guiding further diagnostic steps.
CA125 has a limited role in general population screening for ovarian cancer. It is primarily considered for women at very high risk, such as those with a strong family history or known genetic mutations like BRCA1 or BRCA2. For the general population, CA125 is not recommended as a standalone screening tool due to its lack of specificity, as many non-cancerous conditions can cause elevated levels.
Understanding Your CA125 Test Results
When you receive your CA125 test results, understand that elevated levels do not automatically confirm cancer. A normal CA125 level is generally considered below 35 units per milliliter (U/mL). Levels above this threshold are considered elevated, but such elevations can be attributed to a variety of non-cancerous conditions.
For example, common benign gynecological conditions like endometriosis, where tissue similar to the uterine lining grows outside the uterus, can cause CA125 levels to rise. Uterine fibroids, which are non-cancerous growths of the uterus, and pelvic inflammatory disease, an infection of the female reproductive organs, can also lead to increased CA125. Furthermore, physiological states such as menstruation and pregnancy can temporarily elevate CA125 levels. Even certain liver diseases or other inflammatory conditions can impact CA125 readings. Therefore, a medical professional must interpret these results within the context of your overall health and other diagnostic findings.
The Bigger Picture in Ovarian Cancer Diagnosis
The CA125 test is only one piece of the diagnostic puzzle and is never used as a standalone tool for diagnosing ovarian cancer. A comprehensive diagnosis relies on a combination of different tests and evaluations. This integrated approach ensures a more accurate assessment of a patient’s condition.
The diagnostic process often begins with a thorough pelvic exam, allowing a doctor to feel for any abnormalities in the reproductive organs. This is typically followed by imaging studies, such as a transvaginal ultrasound, which uses sound waves to create images of the ovaries and uterus. More advanced imaging like a CT scan or MRI may also be used to get a detailed view of the pelvic and abdominal organs and to check for any spread of disease.
Ultimately, the definitive diagnosis of ovarian cancer requires a biopsy, where a small tissue sample is surgically removed and examined under a microscope by a pathologist. This microscopic analysis can confirm the presence of cancer cells and determine the type of ovarian cancer. Genetic testing, such as for BRCA mutations, may also be recommended, especially if there is a family history of ovarian or breast cancer, as these mutations can increase risk. Finally, consultation with a gynecologic oncologist, a specialist in cancers of the female reproductive system, is a standard part of the diagnostic and treatment planning process.