Opinion - Whatcom View

POSTED: Saturday, Sep. 19, 2009

Ovarian cancer remains elusive, tests improving

September is Ovarian Cancer Awareness Month, and as such, it is valuable to review what is known and not known about ovarian cancer.

I believe ovarian cancer is the most frightening cancer a woman may get because it is the most difficult cancer to diagnose and it is usually found at a more advanced stage. Thus, it is less likely a woman will survive her ovary cancer than any other cancer she could develop.

All women have a lifetime risk of 1 to 2 percent of getting ovarian cancer. Things that can decrease our risk are the use of birth control pills or other hormonal suppression of ovulation, or having children or nursing children. Things that can increase the risk of developing ovary cancer are increasing age, infertility or heredity. A family history of ovary or bowel or breast cancer may suggest a genetic cause, but, as in breast cancer, only one in 10 women who get ovary cancer can blame it on their genetic heritage.

The most common theory today about what may cause the majority of ovarian cancers is "frequent ovulation." The constant release of eggs from the ovary and the repair that happens to the surface of the ovary after ovulation may be a trigger to developing ovarian cancer.

That being said, it is clear why having children, nursing children, or being on birth control pills may decrease the risk as all these events decrease the number of times a woman's ovaries are actively working or ovulating. Use of birth control pills for more than 5 years can actually decrease a woman's lifetime risk to less than 1 percent.

What all women want, however, is to be able to detect ovary cancer early so that it can be treated successfully. We have pap smears for cervical cancer detection, mammograms for breast cancer and colonoscopy's for colon cancer so what can we use to screen for ovarian cancer? In short, the answer is not as gratifying.

Despite all the media hype that the tumor marker CA 125 is the answer to the question above, in truth, this test's usefulness falls short. The serum CA 125 test is just not specific and accurate enough. Why? While it is true that most advanced ovarian cancers will produce elevated CA 125 levels, many other conditions can also cause this protein to be elevated, such as endometriosis, uterine fibroids, liver disease, colitis, diabetes mellitus and diverticulitis just to name a few. Stated another way, if 100 women had an elevated CA 125, only 3 of them would actually have ovary cancer.

So what about screening with a sonogram or ultrasound? The problem here is that the ovarian physical changes that accompany ovary cancer are just not detectable early. Like it or not, imaging alone is not accurate enough to be a reliable screen.

So what to do? Studies are ongoing to try to find other tumor markers that may be more specific but to date none has been found that performs better than the CA 125 test. Today, the best way to be on the alert for ovary cancer is to combine the three methods we have to try to single out women who may need more close inspection. These three methods are to be alert to the Ovarian Cancer Symptom Index, to use pelvic ultrasound and serum CA 125 tests to improve the accuracy of detection.

The symptoms which should trigger concern are pelvic and /or abdominal pain, bloating, increased size of the abdomen and early satiety more than 12 times a month. Women who experience these symptoms should be examined by an experienced physician, and possibly have both a CA 125 blood test and an ultrasound. If the CA 125 level is elevated and suspicious findings are seen in the ovary such as complex cysts with abnormally increased blood supply and large volumes of free abdominal fluid these women must be examined more aggressively.

So yes, ovary cancer is frightening, but it is important to remember that it really isn't all that common and there are some things that can be done to decrease your risk overall. It is hoped, in time, medical research will reveal other tests that can lead to earlier diagnosis and treatment.

Dr. Cheryl Kellert works for PeaceHealth Medical Group's OB/GYN Clinic. This column is one of an occasional series on health care issues written by members of the Whatcom County Medical Society. If you have a column suggestion for the doctors, send it to wcms@hinet.org