Women's Health

Why Ovarian Cancer is Difficult to Detect Early

Why Ovarian Cancer is Difficult to Detect Early

All too often we hear the term “the silent killer” when describing ovarian cancer. This term has come from the false belief that ovarian cancer is a disease without any warning signs and without much research. However, there is quite a lot of research, in fact, that confirms that most women who come out with a positive diagnosis of ovarian cancer actually experienced several different symptoms from several months to a few years before their diagnosis. What seems like normal symptoms of digestive or urinary issues may actually be symptoms of the early stages of ovarian cancer.

However, this is not to say that ovarian cancer is easy to detect by any means, when it is actually quite difficult to find out that you have it during the earliest stages, when it is the easiest to treat. There are three primary reasons why ovarian cancer is so difficult to treat early: 1) It usually spreads before detection; 2) Limited screening technology; and 3) Limited treatments.

Spreads Before Detection

Any cancer is scary and horrible to hear, but ovarian cancer is even more frightening to women and loved ones because of its high rate of fatality. More than 70 percent of women with ovarian cancer are not diagnosed until their cancer has already reached stage III or stage IV, at which point the cancer is very difficult to cure (Friedman, Sutphen, & Steligo, 2012). However, if a woman is diagnosed with ovarian cancer early on, then her chance at survival is quite good. In fact, if detected at stage I, the survival rate is at least 93 percent (Friedman, Sutphen, & Steligo, 2012). Stage I ovarian cancer tumors are also usually curable through surgical removal and chemotherapy is normally not needed. Unfortunately, as of this publication, there are no reliable methods for early-stage detection. Early stages of ovarian cancer are almost always discovered by accident, usually as part of a preventative surgery (Morris & Gordon, 2010).

Limited Screening Technology

Most experts in the field candidly agree that the current detection and treatment options available are not successful enough. Neither the standards for the pelvic exam, the transvaginal ultrasound, and the method for measuring blood levels of the protein, CA-125, are effective at finding ovarian cancer when it can be easily treated, at stage I (Morris & Gordon, 2010).

Over 93 percent of women who are diagnosed at stage I can be cured, yet less than 20 percent of ovarian cancers are discovered this early (Friedman, Sutphen, & Steligo, 2012). Why? One of the reasons ovarian cancer is so difficult to detect early on is due to women being unaware of the subtle symptoms that come with it. These symptoms include:

As you can see, the symptoms may be subtle and easy to ignore or mistakenly associated with normal menstrual cycles, urinary problems, or digestive issues. However, these symptoms should be considered particularly significant if they are brand new, seem to occur every day or most days, cannot be associated with regular menstrual cycles, or increase in frequency or severity over a prolonged period of time. This is an important time to point out that if your regular doctor treats the symptoms without screening for ovarian cancer, yet your symptoms persist beyond his or her treatment methods, you should seriously consider seeking a second opinion from an actual gynecologic expert. Remember that the best strategy to fighting ovarian cancer, like any type of cancer, is to detect it as early as possible.

Screening

Women who are positive for the BRCA gene, as well as other high-risk women, should be screened regularly for early detection. The National Cancer Institute (NCI) actually recommends that all women over the age of 18 have a transvaginal ultrasound and a CA-125 blood test every six to twelve months.

Pelvic Exam

All adult women are aware of the need for annual pelvic exams. A pelvic exam is usually done along with a Pap smear, which tests for cervical cancer. However, the recommended time frame for women to get a Pap smear often changes, depending on certain risk factors, such as lifestyle or age. It is worth mentioning that a Pap smear does not check for ovarian cancer, although some symptoms, such as issues with the fallopian tube maye show up in one (Morris & Gordon, 2010).

A typical pelvic exam starts with the doctor manually palpating your ovaries (which are the small, almond-sized organs situated inside your lower pelvis). However, even the most experienced experienced gynecologist may miss pretty advanced ovarian cancers (depending on the position of a woman’s reproductive organs and her body type). All too often, by the time a doctor can feel ovarian cancer through a pelvic exam, it is generally in a fairly advanced stage. When combined with transvaginal ultrasounds or CA-125 testing, pelvic exams are much more effective at detecting early stages of ovarian cancer.

Transvaginal Ultrasound (TVU)

The TVU screening method involves the insertion of an ultrasound probe into the vagina that bounces sound waves off of the internal organs of the pelvis and lower abdomen, providing an image of the insides. While TVU’s give a good and clear image of the condition of the ovaries, it is still not a reliable indicator of ovarian cancer. The reason for this is the high rate of false positives that appear to be abnormalities, but are, in fact nothing more than signs of ovulation. TVU’s are also not very good at detecting ovarian cancer early on, but are more likely to detect stage III or higher.

The NCI is currently researching the effectiveness of TVU both against and in combination with the CA-125 test. So far, results suggest that combining TVU with the CA-125 test may lead to at least 50 percent of postmenopausal women of average risk being detected within stage I or stage II, but no confirmed results have been published to date (Morris & Gordon, 2010).

CA-125

CA-125 (or cancer antigen-125) is a special protein that is produced and released into the bloodstream in higher concentrations by cancerous ovarian cells than by normal, healthy cells. Your doctor starts the test by collecting a sample of your blood and sending it to the lab for results. Within a few days, your doctor should be able to tell you the results. The results will be described as a number of units per milliliter (U/ml). Any number greater than 35 U/ml is usually said to be an elevated CA-125 reading, though each particular lab may use a slightly different value system so the exact number may vary.

Unfortunately, research has shown that a single CA-125 test alone is not effectiveness enough to detect ovarian cancer. However, by repeating the test at regular intervals (often called serial testing), your doctor may be able to detect a telling trend. Like TVU’s, CA-125 tests can also show a false positive. This is because there are many other diseases (such as endometriosis, benign cysts, and pregnancy) may also cause your CA-125 level to rise.

Blood Tests

Similar to breast cancer, most of the research surrounding ovarian cancer is on trying to develop blood tests that can accurately detect patients during the earliest stages. Currently, the CA-125 is the only ovarian cancer blood test approved by the Food and Drug Administration (FDA). There are, however, several other tests that are currently still in their research phases of development. For example, there are a few research projects that are focused on the study of proteins (such as CA-125) and their functions in the body and with cancers (also called proteomics). One such study by Yale, utilizes a panel of six proteins that they claim can detect early-stage ovarian cancer accurately 91 percent of the time.

Additional Resources

National Cancer Institute www.cancernet.nci.nih.gov

The National Cancer Institute web site has some of the most recent cancer information and news from the National Cancer Institute. This agency is headed by the U.S. Department of Health and Human Services.

American Cancer Society www.cancer.org

With over 2 million volunteer and over 3,000 local chapters, the ACS works endlessly to end cancer through prevention, saving lives, education, and advocacy.

Cancer Care, Inc. www.cancercare.org

This nonprofit organization began in 1994 to offer emotional support, information, practical help, and additional support to help people with all types of cancer and their loved ones find hope and live full lives after a diagnosis.

References

Bigenwald, R.Z. (2008). Is Mammography Adequate for Screening Women with Inherited BRCA Mutations and Low Breast Density? In Cancer Epidemiology Biomarkers & Prevention 17. No. 3: 706-11.

Friedman, S., Sutphen, R., and Steligo, K. (2012). Confronting Hereditary Breast and Ovarian Cancer. The John Hopkins University Press. Baltimore, Maryland.

Morris, J.L. & Gordon, O.K. (2010). Positive Results: Making the Best Decisions When You’re at High Risk for Breast or Ovarian Cancer. Prometheus Books. Amherst, New York.