Ovarian cancer: ‘Kathy’s Story’ not the answer

Several times each year I get questions about a blood test called CA-125. Usually these questions are in response to an e-mail that has been circulating for nearly a decade. It tells "Kathy's Story." Kathy is actually Carolyn Benivegna, a real woman living in Florida who had cancer.

According to her story, she had great difficulty getting doctors to take her seriously enough to make a diagnosis. The cancer turned out to be ovarian cancer and "Kathy" went public with her story, encouraging every single woman in the world to demand a CA-125 test at every annual exam. She warned women: "Doctors will try to deny you this test! Do not let them deny you a simple, low-cost blood test that could save your life! Fight for it!"

I tread carefully here. Of course I would never deny a woman any test that could save her life. Ovarian cancer is a disease that strikes fear in both doctors and patients; it is relatively rare, difficult to diagnose and often found too late. In the U.S., only about 1 woman in 57 is diagnosed in her lifetime with this type of cancer (compared to 1 in 8 women who will get breast cancer). But of the roughly 22,000 new cases we will see in 2007, more than 15,000 will be fatal.

Every doctor I know would like to have an easy way to screen for ovarian cancer, and researchers are working on developing just such a test. But CA-125 isn't it.

CA-125 (Cancer Antigen 125) is a protein that is found on the surface of cells in the ovaries, the cervix, the fallopian tubes, and in the lining of the chest and the abdomen.

It would make sense that elevated levels of CA-125 could indicate ovarian cancer if it were specific to the ovaries, but it is not. This antigen can also indicate normal menstruation, endometriosis, fibroids, pelvic infections, liver disease, benign ovarian cysts, pregnancy, liver cirrhosis and many other types of cancer. It can also be elevated in perfectly healthy individuals.

A doctor who is reluctant to order this test for general screening is only practicing good medicine. Fifty percent of the time, CA-125 misses early-stage ovarian cancer altogether, allowing patients to think they are just fine when really they need to be starting aggressive treatment immediately.

On the other hand, by yielding many false positive results this test also causes tremendous panic and unnecessary surgeries.

Granted, it is still a helpful test for a few particular situations. Serial testing can help monitor cancer that has already been diagnosed. But CA-125 is not a good initial screening tool in the way "Kathy's Story" insists it can be.

Until we develop a simple blood screening test, diagnosis of ovarian cancer relies on symptoms reported to an attentive physician. These are symptoms that every woman should know. Most common are a combination of persistent bloating, pelvic or abdominal pain, difficulty eating or feeling full quickly, pain during intercourse, and problems with urination.

These particular complaints can be pretty vague and make ovarian cancer a diagnosis sometimes missed while "wasting time" treating for indigestion, urinary tract infections, and other more benign possible causes. Reporting these symptoms, allowing your doctor to examine your pelvis and getting an ultrasound specific for the ovaries is currently the most common way to make the diagnosis of ovarian cancer.

Women can decrease their risk of developing ovarian cancer by avoiding obesity, by having a child and breastfeeding the baby for a year or more or by getting a tubal ligation. Taking birth control pills may also decrease a woman's risk.

The physiologic mechanism of these protective measures is not clearly understood, but is probably due to changes in lifetime ovarian gland activity.

Some high-risk women (women with close relatives who have had ovarian cancer, or women with genetic risk factors) have opted for prophylactic removal of both ovaries, but these women are still left with managing an early menopause and a remaining 5 percent risk of developing ovarian cancer from surrounding tissues.

In 2000, Benivegna posted a revision of her earlier e-mail, but the original still persists. It is dramatic and angry, it reads well, sounds real, and sometimes comes with famous people's names attached for veracity.

Don't fall for it. Be smart, read up on the current information about ovarian cancer, and work with your doctor to get what you really need.

Dr. Stacey Kerr, a longtime Sonoma County family physician, graduated from UC Davis Medical School and is certified in her specialty by the American Board of Family Medicine. Her columns are not intended as a substitute for hands-on medical advice or treatment. Consult your health care provider before adhering to any recommendations in this column.

E-mail comments to drkerr@the-doctors-inn.com.