A Way To Screen for Ovarian Cancer?

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Looking at the rate of change in a blood test may be a good way to screen healthy women for ovarian cancer, a new study suggests. This form of cancer usually is diagnosed late, when it is hard to cure. The new study included a test for the protein CA-125. Blood levels are high in many women with ovarian cancer. But this protein can be high for other reasons, too. More than 3,200 older women were tested for CA-125. Researchers calculated each woman's risk based on her CA-125 level and how it changed over time. Women at low risk were tested each year. Medium-risk women got tests every three months. The study lasted nine years. In this time, 85 women with the highest risk received ultrasound tests to look for signs of cancer. Eight of them were referred for surgery. The surgery found three invasive cancers, all in early stages. Two women had "borderline" tumors. Three had tumors that were not cancer. Researchers presented results at a news conference on May 21.

What Is the Doctor's Reaction?

Ovarian cancer is not common, but it's one of the cancers that often lead to early death. In 2009, about 21,550 American women were diagnosed with ovarian cancer. About 14,600 died of the disease.

Compare that with prostate cancer in 2009. More than 192,000 American men were diagnosed with prostate cancer. More than 27,300 died of the disease.

Ovarian cancer is five times as deadly as prostate cancer.

Most men with prostate cancer do not die from the cancer, even if they never get treated. Ovarian cancer is completely different. Without treatment, women with ovarian cancer will almost always die as a direct result of the cancer.

Early detection makes a huge difference in survival. About 75% of cases are diagnosed late, after the cancer has spread beyond the ovaries. Often, it has spread throughout the abdomen as well. At that point, the 5-year survival rate is less than 30%.

For the 25% of cases that are diagnosed early, the outlook is very different. The 5-year survival rate is more than 90%.

This large difference in survival means that effective screening could save a lot of lives. The two tests that have held the most promise for early detection are a blood test called CA-125 and transvaginal ultrasound. However, much more often than not, cancer is not the cause of abnormal results in these two tests. The result: Many women have surgeries they don't need.

The results of this new study suggest that these two tests might still be useful. But the team led by Karen Lu, M.D., used a different strategy in with the tests. They did not just look at whether the CA-125 level was normal or abnormal. They also considered whether CA-125 rose over time.

This strategy might increase the rate of early detection of ovarian cancer. However, 2 out of every 3 women who have surgery will not have cancer. Also, some cancers can be missed. That's because CA-125 can be normal in more than 20% of early-stage ovarian cancers.

What Changes Can I Make Now?

Screening with CA-125 and/or transvaginal ultrasound may make sense for some women. These would include women whose mother, sister, daughter, grandmother, aunt or niece had ovarian cancer. Carriers of the BRCA1 or BRCA2 gene mutations are at very high risk.

Many experts recommend that high-risk women have a CA-125 test and transvaginal ultrasound every six months. High-risk women who are past childbearing age often choose to have their ovaries removed. This procedure is 90% effective in preventing ovarian cancer.

For women at average risk, routine screening is not recommended. Pay attention to certain new symptoms that persist for three or more weeks:

• Bloating or swelling of your belly, especially in the lower half


• Pelvic or abdominal pain or pressure


• Loss of appetite or feeling full after a few bites


• Frequent or urgent urination (feeling like you have to go right away)

These symptoms are not always caused by ovarian cancer. In fact, it is unlikely that ovarian cancer will be the cause, even if you have all four of these symptoms. Still, you should contact your doctor if they persist.

What Can I Expect Looking to the Future?

Researchers are actively looking for better ways to detect ovarian cancer at an earlier stage. However, progress has been minimal. So far, no study, including this latest one, has shown a satisfactory way to detect ovarian cancer early in women at average risk for the disease.

But we should remain optimistic that scientists will discover a cost-effective way to find early ovarian cancers. The reason for optimism: This is a cancer for which early detection truly can be life-saving. And scientists already have found many possible blood proteins and gene mutations linked with ovarian cancer. It's just a matter of time before one or more of them works.