Cancer Answers: Is There a Screening Test for Ovarian Cancer?
Symptoms of ovarian cancer do not present themselves within early stages and in most cases, ovarian cancer is not detected during routine pelvic examinations.
For this reason, most women with ovarian cancer are diagnosed at an advanced stage – stage III or stage IV – at which case the cancer proves difficult to cure. According to the National Cancer Institute, over 22,000 women between the ages of 35 and 74 will be diagnosed with the disease this year alone. This raises a couple of important questions—Is it possible to be screened for ovarian cancer? And is it ever too early? Screening as a preventive measure may prove dangerous for the patient. It's important to understand when screening for ovarian cancer is worth the risk.
Screening for ovarian cancer
A screening test may be helpful in detecting ovarian cancer and catching the cancer before it spreads. However, there are both benefits and risks associated with undergoing screening tests. The potential benefit of undergoing a screening test for ovarian cancer is that there is a chance of finding the cancer at a stage where it is curable. On the other hand, the potential risk of undergoing a screening test for ovarian cancer is false positive results. A false positive test indicates that a woman has ovarian cancer when she actually does not have the disease. This, in turn, may lead to unnecessary procedures such as surgery, as well as a risk of complications, stress, financial burden, and unnecessary time away from work.
When should I undergo a screening test?
Around 20% of ovarian cancers are found at an early stage. Several studies indicate that the best approach to detecting ovarian cancer at an early stage is to undergo screening tests if you are at high risk of the disease.
- You should be screened if you are at high risk due to a personal history of ovarian cancer or breast cancer.
- You should be screened if you are at high risk due to a family history of ovarian cancer or breast cancer.
- You should be screened if you are predisposed to BRCA1 and BRCA2 gene mutations.
- You should be screened if you are predisposed to genes linked to hereditary nonpolyposis colorectal cancer.
What screening tests are available?
While there are yet no designated screening tests available to detect ovarian cancer, the following tests are often recommended, especially for women at high risk of the disease:
- Pelvic exam - A pelvic exam is a physical examination of the female reproductive organs. More specifically, it can be divided into internal and external examination.
- Transvaginal ultrasound - A transvaginal ultrasound involves the use of sound waves to generate an image of the organs within the pelvis, including the ovaries. A transvaginal ultrasound may find anywhere between 80-100% of ovarian cancers; however, due to the fact that it cannot differentiate between ovarian cancer and other common medical conditions, it is not recommended as a sole detection tool and therefore should be used alongside other methods.
- CA-125 test - CA-125 is a protein that is seen in a higher percentage in over 80% of women with ovarian cancer and it can be measured via a blood test. While it is a useful test in detecting ovarian cancer, similarly to a pelvic exam, it too cannot differentiate between ovarian cancer and other common medical conditions such as endometriosis, pelvic infection, uterine fibroids, and other cancers. For this reason, it is not recommended as a sole detection tool.
“The transition from a normal ovary to an invasive cancer may be less than a year. The concern is that the very early precancerous changes may be very difficult to detect with either the ultrasound or the CA-125,” said Dr. Joseph A. Lucci, a professor and director of gynecologic oncology at the University of Miami Sylvester Comprehensive Cancer Center. Nowadays, several studies have found that combination of a pelvic exam with a CA-125 test may be useful in detecting ovarian cancer in women at high risk of the disease.
When are the screening tests worth the risk?
The transvaginal ultrasound and CA-125 test may be helpful if you are experiencing persistent symptoms of ovarian cancer. What’s more, if your doctor senses something abnormal during your physical examination, these tests may be useful in diagnosing the problem. In any case, it is important that you talk with your doctor about the benefits and risks associated with screening tests and which one is right for you.
What should I do if the screening tests are positive?
If any of the screening tests that you have performed are positive, you should consult with a gynecologic oncologist. He or she may conduct a CT scan in order to confirm the results. Moreover, a biopsy may be recommended to confirm your ovarian cancer diagnosis, and from there, appropriate treatment methods are recommend based on your overall wellbeing.
Am I at risk for ovarian cancer?
If you are concerned that you may have ovarian cancer, it is important that you listen to your body and pay attention to any early and consistent symptoms that may present themselves. Such symptoms may include:
- Feeling bloated
- Experiencing abdominal pain or discomfort
- Having difficulty eating
- Feeling the need to urinate frequently and with heightened urgency
Furthermore, factors that may increase your risk of ovarian cancer include the following:
- Being of an older age
- Being overweight
- Having a family history of female reproductive cancers
- Having BRCA1 and BRCA2 gene abnormalities
- Never having given birth
While early stage symptoms can be rather difficult to uncover, they are not always silent. If any of the above symptoms persist, it is crucial to consult with a specialist so that he or she can perform a screening test.
What does future research on ovarian cancer indicate?
Over the last 20 years, a lot of progress has been made in reference to ovarian cancer. Last year, a study led by Dr. Ian Jacobs followed the measurements of women who underwent a CA-125 blood test. As we discussed, a CA-125 blood test is a well-known tumor marker in several cases of ovarian cancer. The primary results of the study indicated that it is possible to detect ovarian cancer at an early stage. Dr. Jacobs and his colleagues stressed, however, that further analysis needs to be conducted for more accurate results. They will be publishing follow-up results in the near future in order to better inform patients, physicians, and the public about diagnosing ovarian cancer.
Nowadays, screening patients with ovarian cancer for genetic mutations is considered a standard practice in the United States. Dr. Jacobs and his colleagues stress that this standard of practice will allow for a better understanding of the genetic origin of ovarian cancer, as well as help improve future screening tests. Moreover, it will help identify patients who may greatly benefit from a new class of drugs, known as PARP inhibitors. In fact, in recent studies, these oral medications have shown immense improvements in survival rates of women who have experienced ovarian cancer recurrence. Needless to say, the last few years have proved to be a promising time for women affected by ovarian cancer. Research on new ovarian cancer screening tests is ongoing and much effort has been put forward towards identifying new medications and treatment methods.
References
https://www.statnews.com/2016/09/07/ovarian-cancer-screening-test/
http://ovarian.org/about-ovarian-cancer/how-am-i-diagnosed
https://www.cancer.org/cancer/ovarian-cancer/detection-diagnosis-staging/detection.html
https://www.uptodate.com/contents/ovarian-cancer-screening-beyond-the-basics
https://www.livescience.com/14450-ovarian-cancer-screening-tests-reduce-deaths.html
