Part of
Tumour associated markers
Part of
Tumour associated markers
Blood biomarker
Part of
Tumour associated markers
Cancer Antigen 125 (CA 125)
Cancer Antigen 125 (CA 125)
Cancer Antigen 125 (CA 125) is a protein found in blood that can used to help diagnose and monitor ovarian cancer.
Cancer Antigen 125 (CA 125) is a protein found in blood that can used to help diagnose and monitor ovarian cancer.
Cancer Antigen 125 (CA 125)
Normal range
Normal range
<35 kU/L
<35 kU/L
Normal range
<35 kU/L
<35 kU/L
Normal range
Cancer Antigen 125 (CA 125)
Cancer Antigen 125 (CA 125)
Cancer Antigen 125 (CA 125) is a protein found in blood that can used to help diagnose and monitor ovarian cancer.
Cancer Antigen 125 (CA 125)
Normal range
<35 kU/L
Normal range
<35 kU/L
<35 kU/L
Normal range
Cancer Antigen 125 (CA 125)
Cancer Antigen 125 (CA 125)
Cancer Antigen 125 (CA 125) is a protein found in blood that can used to help diagnose and monitor ovarian cancer.
Cancer Antigen 125 (CA 125)
Normal range
<35 kU/L
Normal range
<35 kU/L
<35 kU/L
Normal range
Cancer Antigen 125 (CA 125)
Dr. Daniel McNally
MBBS
The Ovarian Health Indicator
The Ovarian Health Indicator
CA 125 is a protein found in the blood that can reveal important information about what's happening in your body, particularly around your reproductive organs. While it's not a perfect test, CA 125 levels can help doctors monitor certain conditions and guide treatment decisions when used alongside other information.
CA 125 (Cancer Antigen 125) is produced by cells in several tissues, including the ovaries, fallopian tubes, and lining of the abdomen. When these tissues are irritated, inflamed, or abnormal, CA 125 levels in your blood can rise.
CA 125 is a protein found in the blood that can reveal important information about what's happening in your body, particularly around your reproductive organs. While it's not a perfect test, CA 125 levels can help doctors monitor certain conditions and guide treatment decisions when used alongside other information.
CA 125 (Cancer Antigen 125) is produced by cells in several tissues, including the ovaries, fallopian tubes, and lining of the abdomen. When these tissues are irritated, inflamed, or abnormal, CA 125 levels in your blood can rise.
What Can Raise Your CA 125 Levels?
What Can Raise Your CA 125 Levels?
What Can Raise Your CA 125 Levels?
Discover the range of conditions—from everyday issues to serious diseases—that can elevate this important marker.
Read more
Why CA 125 Isn't a Perfect Cancer Screen
Why CA 125 Isn't a Perfect Cancer Screen
Why CA 125 Isn't a Perfect Cancer Screen
Learn why doctors don't use CA 125 alone for cancer screening and what other factors must be considered.
Read more
When Doctors Order CA 125 Testing
When Doctors Order CA 125 Testing
When Doctors Order CA 125 Testing
Find out the specific symptoms and situations that prompt healthcare providers to check your CA 125 levels.
Read more
Understanding Your Results
Understanding Your Results
Understanding Your Results
Understand what the numbers mean and why context matters more than the result alone.
Read more
What Can Raise Your CA 125 Levels?
CA 125 levels can increase for many reasons, and most of them aren't cancer. Understanding this is crucial because elevated levels often cause unnecessary anxiety when the cause is actually something much more manageable.
Common non-cancer causes include:
Menstruation (levels naturally fluctuate with your cycle)
Pregnancy, especially in the first trimester
Endometriosis, where tissue similar to the uterine lining grows elsewhere
Ovarian cysts, particularly large or multiple cysts
Pelvic inflammatory disease and infections
Liver disease, including cirrhosis or hepatitis
Heart failure or other conditions causing fluid retention
Recent abdominal surgery or procedures
More serious causes include:
Ovarian cancer (the primary reason doctors check CA 125)
Other cancers affecting the abdomen, such as pancreatic, liver, or colon cancer
Peritoneal cancer (cancer of the abdominal lining)
Advanced endometrial (uterine) cancer
The key point is that CA 125 is more of a "something's happening" signal rather than a "cancer" signal. Many women with elevated CA 125 levels have benign conditions that can be effectively treated, if at all.
What Can Raise Your CA 125 Levels?
CA 125 levels can increase for many reasons, and most of them aren't cancer. Understanding this is crucial because elevated levels often cause unnecessary anxiety when the cause is actually something much more manageable.
Common non-cancer causes include:
Menstruation (levels naturally fluctuate with your cycle)
Pregnancy, especially in the first trimester
Endometriosis, where tissue similar to the uterine lining grows elsewhere
Ovarian cysts, particularly large or multiple cysts
Pelvic inflammatory disease and infections
Liver disease, including cirrhosis or hepatitis
Heart failure or other conditions causing fluid retention
Recent abdominal surgery or procedures
More serious causes include:
Ovarian cancer (the primary reason doctors check CA 125)
Other cancers affecting the abdomen, such as pancreatic, liver, or colon cancer
Peritoneal cancer (cancer of the abdominal lining)
Advanced endometrial (uterine) cancer
The key point is that CA 125 is more of a "something's happening" signal rather than a "cancer" signal. Many women with elevated CA 125 levels have benign conditions that can be effectively treated, if at all.
What Can Raise Your CA 125 Levels?
CA 125 levels can increase for many reasons, and most of them aren't cancer. Understanding this is crucial because elevated levels often cause unnecessary anxiety when the cause is actually something much more manageable.
Common non-cancer causes include:
Menstruation (levels naturally fluctuate with your cycle)
Pregnancy, especially in the first trimester
Endometriosis, where tissue similar to the uterine lining grows elsewhere
Ovarian cysts, particularly large or multiple cysts
Pelvic inflammatory disease and infections
Liver disease, including cirrhosis or hepatitis
Heart failure or other conditions causing fluid retention
Recent abdominal surgery or procedures
More serious causes include:
Ovarian cancer (the primary reason doctors check CA 125)
Other cancers affecting the abdomen, such as pancreatic, liver, or colon cancer
Peritoneal cancer (cancer of the abdominal lining)
Advanced endometrial (uterine) cancer
The key point is that CA 125 is more of a "something's happening" signal rather than a "cancer" signal. Many women with elevated CA 125 levels have benign conditions that can be effectively treated, if at all.
Why CA 125 Isn't a Perfect Cancer Screen
CA 125 has both strengths and limitations, which is why its use in asymptomatic women requires careful consideration. Understanding these nuances helps manage interpretation of this test.
The sensitivity considerations: CA 125 is most reliable in detecting advanced ovarian cancer, with about 80-90% of women with advanced disease having elevated levels. However, only about 50% of women with early-stage disease show elevation, which presents challenges for early detection programs.
The ‘false alarm’ challenge: Many benign conditions can elevate CA 125 levels, particularly in pre-menopausal women. This means some women with elevated levels will require additional testing to determine the cause, though modern imaging and clinical assessment can usually distinguish between benign and concerning findings effectively.
The evolving landscape: Research continues into combination approaches that use CA 125 alongside other biomarkers, imaging, and risk assessment tools. Some screening programs use sophisticated algorithms that account for individual risk factors and trends in CA 125 levels over time.
While routine population screening remains debated, CA 125 testing can provide valuable information when used thoughtfully as part of comprehensive health assessment, particularly in higher-risk women or when combined with other diagnostic approaches.
Why CA 125 Isn't a Perfect Cancer Screen
CA 125 has both strengths and limitations, which is why its use in asymptomatic women requires careful consideration. Understanding these nuances helps manage interpretation of this test.
The sensitivity considerations: CA 125 is most reliable in detecting advanced ovarian cancer, with about 80-90% of women with advanced disease having elevated levels. However, only about 50% of women with early-stage disease show elevation, which presents challenges for early detection programs.
The ‘false alarm’ challenge: Many benign conditions can elevate CA 125 levels, particularly in pre-menopausal women. This means some women with elevated levels will require additional testing to determine the cause, though modern imaging and clinical assessment can usually distinguish between benign and concerning findings effectively.
The evolving landscape: Research continues into combination approaches that use CA 125 alongside other biomarkers, imaging, and risk assessment tools. Some screening programs use sophisticated algorithms that account for individual risk factors and trends in CA 125 levels over time.
While routine population screening remains debated, CA 125 testing can provide valuable information when used thoughtfully as part of comprehensive health assessment, particularly in higher-risk women or when combined with other diagnostic approaches.
Why CA 125 Isn't a Perfect Cancer Screen
CA 125 has both strengths and limitations, which is why its use in asymptomatic women requires careful consideration. Understanding these nuances helps manage interpretation of this test.
The sensitivity considerations: CA 125 is most reliable in detecting advanced ovarian cancer, with about 80-90% of women with advanced disease having elevated levels. However, only about 50% of women with early-stage disease show elevation, which presents challenges for early detection programs.
The ‘false alarm’ challenge: Many benign conditions can elevate CA 125 levels, particularly in pre-menopausal women. This means some women with elevated levels will require additional testing to determine the cause, though modern imaging and clinical assessment can usually distinguish between benign and concerning findings effectively.
The evolving landscape: Research continues into combination approaches that use CA 125 alongside other biomarkers, imaging, and risk assessment tools. Some screening programs use sophisticated algorithms that account for individual risk factors and trends in CA 125 levels over time.
While routine population screening remains debated, CA 125 testing can provide valuable information when used thoughtfully as part of comprehensive health assessment, particularly in higher-risk women or when combined with other diagnostic approaches.
When Doctors Order CA 125 Testing
CA 125 testing is typically ordered in specific clinical situations where the information will help guide medical decisions. Understanding when and why doctors use this test can help you better interpret your results.
Symptom evaluation: If you have symptoms that could suggest ovarian cancer—such as persistent abdominal bloating, pelvic pain, or unexplained weight loss—your doctor might order CA 125 as part of the evaluation process.
Cancer monitoring: For women diagnosed with ovarian cancer, CA 125 becomes an important tool for monitoring treatment response. Levels typically fall during successful treatment.
Pre-surgical evaluation: Before surgery for pelvic masses, CA 125 levels can help surgeons plan the procedure and determine whether specialist oncology input is needed.
The key is that CA 125 is most informative in context—alongside symptoms, physical examination findings, imaging results, and your personal medical history.
When Doctors Order CA 125 Testing
CA 125 testing is typically ordered in specific clinical situations where the information will help guide medical decisions. Understanding when and why doctors use this test can help you better interpret your results.
Symptom evaluation: If you have symptoms that could suggest ovarian cancer—such as persistent abdominal bloating, pelvic pain, or unexplained weight loss—your doctor might order CA 125 as part of the evaluation process.
Cancer monitoring: For women diagnosed with ovarian cancer, CA 125 becomes an important tool for monitoring treatment response. Levels typically fall during successful treatment.
Pre-surgical evaluation: Before surgery for pelvic masses, CA 125 levels can help surgeons plan the procedure and determine whether specialist oncology input is needed.
The key is that CA 125 is most informative in context—alongside symptoms, physical examination findings, imaging results, and your personal medical history.
When Doctors Order CA 125 Testing
CA 125 testing is typically ordered in specific clinical situations where the information will help guide medical decisions. Understanding when and why doctors use this test can help you better interpret your results.
Symptom evaluation: If you have symptoms that could suggest ovarian cancer—such as persistent abdominal bloating, pelvic pain, or unexplained weight loss—your doctor might order CA 125 as part of the evaluation process.
Cancer monitoring: For women diagnosed with ovarian cancer, CA 125 becomes an important tool for monitoring treatment response. Levels typically fall during successful treatment.
Pre-surgical evaluation: Before surgery for pelvic masses, CA 125 levels can help surgeons plan the procedure and determine whether specialist oncology input is needed.
The key is that CA 125 is most informative in context—alongside symptoms, physical examination findings, imaging results, and your personal medical history.
Understanding Your Results
CA 125 results must be interpreted carefully, considering individual circumstances, symptoms, and other test results. The number alone doesn't tell the whole story.
Normal ranges:
Below 35 U/mL
CA 125 levels are typically lower and more stable in post-menopausal women, making elevations potentially more significant than in pre-menopausal women.
Remember that CA 125 results must be considered alongside other factors. A high level with concerning symptoms and imaging findings has different implications than an isolated high level in someone with no symptoms. Context is important.
Understanding Your Results
CA 125 results must be interpreted carefully, considering individual circumstances, symptoms, and other test results. The number alone doesn't tell the whole story.
Normal ranges:
Below 35 U/mL
CA 125 levels are typically lower and more stable in post-menopausal women, making elevations potentially more significant than in pre-menopausal women.
Remember that CA 125 results must be considered alongside other factors. A high level with concerning symptoms and imaging findings has different implications than an isolated high level in someone with no symptoms. Context is important.
Understanding Your Results
CA 125 results must be interpreted carefully, considering individual circumstances, symptoms, and other test results. The number alone doesn't tell the whole story.
Normal ranges:
Below 35 U/mL
CA 125 levels are typically lower and more stable in post-menopausal women, making elevations potentially more significant than in pre-menopausal women.
Remember that CA 125 results must be considered alongside other factors. A high level with concerning symptoms and imaging findings has different implications than an isolated high level in someone with no symptoms. Context is important.
The Takeaway
CA 125 is a valuable but imperfect tool in women's healthcare. While it can provide important information in a clinical context, it's not a standalone screening test and must be interpreted carefully within the context of your overall health picture.
Most women with elevated CA 125 levels have benign conditions that can be effectively managed. However, the test serves an important role in recognising issues, monitoring certain conditions, and tracking treatment responses in women with ovarian cancer.
If you have symptoms like persistent abdominal bloating, pelvic pain, or unexplained weight loss, don't wait to seek medical attention. These symptoms warrant evaluation regardless of CA 125 levels, and early assessment can lead to earlier treatment, if necessary.
The Takeaway
CA 125 is a valuable but imperfect tool in women's healthcare. While it can provide important information in a clinical context, it's not a standalone screening test and must be interpreted carefully within the context of your overall health picture.
Most women with elevated CA 125 levels have benign conditions that can be effectively managed. However, the test serves an important role in recognising issues, monitoring certain conditions, and tracking treatment responses in women with ovarian cancer.
If you have symptoms like persistent abdominal bloating, pelvic pain, or unexplained weight loss, don't wait to seek medical attention. These symptoms warrant evaluation regardless of CA 125 levels, and early assessment can lead to earlier treatment, if necessary.
The Takeaway
CA 125 is a valuable but imperfect tool in women's healthcare. While it can provide important information in a clinical context, it's not a standalone screening test and must be interpreted carefully within the context of your overall health picture.
Most women with elevated CA 125 levels have benign conditions that can be effectively managed. However, the test serves an important role in recognising issues, monitoring certain conditions, and tracking treatment responses in women with ovarian cancer.
If you have symptoms like persistent abdominal bloating, pelvic pain, or unexplained weight loss, don't wait to seek medical attention. These symptoms warrant evaluation regardless of CA 125 levels, and early assessment can lead to earlier treatment, if necessary.
References
American Cancer Society. (2020). Ovarian cancer screening and early detection. Cancer Facts & Figures.
Royal College of Obstetricians and Gynaecologists. (2019). The management of ovarian cysts in postmenopausal women. RCOG Green-top Guideline.
National Institute for Health and Care Excellence. (2018). Ovarian cancer: recognition and initial management. NICE Clinical Guideline.
References
American Cancer Society. (2020). Ovarian cancer screening and early detection. Cancer Facts & Figures.
Royal College of Obstetricians and Gynaecologists. (2019). The management of ovarian cysts in postmenopausal women. RCOG Green-top Guideline.
National Institute for Health and Care Excellence. (2018). Ovarian cancer: recognition and initial management. NICE Clinical Guideline.
References
American Cancer Society. (2020). Ovarian cancer screening and early detection. Cancer Facts & Figures.
Royal College of Obstetricians and Gynaecologists. (2019). The management of ovarian cysts in postmenopausal women. RCOG Green-top Guideline.
National Institute for Health and Care Excellence. (2018). Ovarian cancer: recognition and initial management. NICE Clinical Guideline.
Research articles
Research articles
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