From the Guidelines
There is no reliable blood test for routine ovarian cancer screening in the general population. The CA-125 blood test, which measures a protein that can be elevated in ovarian cancer, is not recommended for general screening because it can be elevated in many non-cancerous conditions (like endometriosis, fibroids, or menstruation) and may not be elevated in early-stage ovarian cancer 1.
Key Points to Consider
- For high-risk women, such as those with BRCA1/BRCA2 gene mutations or strong family histories of ovarian cancer, doctors may use CA-125 testing along with transvaginal ultrasound for surveillance, but even this combination has limitations in detecting early disease 1.
- Research is ongoing for more effective screening methods, including panels of multiple biomarkers and more sensitive tests.
- If you're concerned about ovarian cancer risk, the best approach is to discuss your personal and family history with your doctor, who can assess your risk factors and recommend appropriate monitoring strategies.
- Be aware of symptoms like persistent bloating, pelvic pain, difficulty eating, and frequent urination, as these warrant prompt medical evaluation.
Limitations of Current Screening Methods
- The PLCO Cancer Screening Trial found that screening average-risk, asymptomatic women with serum CA-125 testing and transvaginal ultrasonography does not reduce ovarian cancer deaths 1.
- Harms associated with screening for ovarian cancer have been reported, including false-positive results and unnecessary surgeries 1.
Future Directions
- Ongoing research aims to develop more effective screening methods, including the use of multiple biomarkers and more sensitive tests.
- The UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) is assessing multimodality screening with ultrasound and CA-125 versus either ultrasound alone or no screening 1.
From the Research
Blood Test for Ovarian Cancer Screen
- The primary ovarian cancer marker used for the past four decades is the tumour biomarker CA125 2.
- Screening average-risk asymptomatic women with CA125 is not recommended by any professional society due to the low sensitivity and specificity of the test in detecting early-stage ovarian cancer 2, 3, 4.
- The combination of CA125 and transvaginal ultrasound (TVU) has been shown to have a higher sensitivity and specificity than CA125 alone, but still has limitations in detecting early-stage ovarian cancer 3, 5, 6.
- A study found that the sensitivity and specificity of CA125 and TVU were 40% and 99%, respectively, with a positive predictive value (PPV) of 40% and a negative predictive value (NPV) of 99% 3.
- Another study identified high-risk categories for predicting the risk of ovarian cancer in women with abnormal CA125 and TVU results, with a sensitivity of 60-85% and specificity of 95-96% 6.
- The use of point-of-care CA125 assays in primary care facilities may provide a new and valuable target for screening, particularly for low-volume type II ovarian cancer in its early stages of evolution 2.
- Prophylactic surgery to remove the fallopian tubes and ovaries is recommended for high-risk women, such as those with BRCA1 or BRCA2 mutations, to prevent 90% of ovarian cancers 4, 5.