Women urged to monitor symptoms of ovarian cancer

While search continues for effective screening test, other steps may be needed, too

By Dennis Thompson
HealthDay Reporter

(HealthDay News) -- Attempts to find a screening test for ovarian cancer experienced both an advance and a setback in recent months.

British researchers announced in March that the combination of an ultrasound examination and a blood test successfully detected ovarian cancer in 90 percent of the women they tested who had the disease. What's more, half of those cancers were found in their early stage, which is important because early treatment is crucial to better chances of survival.

But days later, an American study threw cold water on the news. Those researchers reviewed the same screening regimen and found that it did not detect ovarian cancers early enough to make a difference in mortality rates.

The development was somewhat typical of ovarian cancer, which has resisted researchers' attempts to develop a screening process that could save lives.

"It looks like ovarian cancer is not like breast cancer, which starts and then progresses at a steady rate," said Debbie Saslow, director of breast and gynecologic cancers at the American Cancer Society. "At least half the experts in this field have argued that women with early-stage ovarian cancer have a very slow-growing cancer that rapidly increases growth as it enters its later stages. There's literally no time to detect it early, remove the ovaries and have successful treatment."

Ovarian Cancer Awareness Month, observed in September, gives doctors and researchers a chance to share what they know about the deadly illness and discuss how close they are to improving survival rates among women.

About 21,550 new cases of ovarian cancer will be diagnosed in the United States during 2009, according to the American Cancer Society. Ovarian cancer makes up about 3 percent of all cancers in women.

That makes it a rare cancer, which means it is difficult to create a test accurate enough to make the screenings medically worthwhile, said Dr. Barbara Goff, director of gynecologic oncology at the University of Washington School of Medicine.

"One in every 2,500 women will get ovarian cancer each year, over age 50," Goff said. "The risk is very small that any one person will get ovarian cancer. You have to do so many screens before you detect even one case of ovarian cancer. It's not very cost-effective."

Nonetheless, the search for a screening test for ovarian cancer continues. About 14,600 women will die from ovarian cancer in the United States during 2009, and many of those lives could have been saved if a test could find the cancer in its early stage.

Saslow said that researchers are pulling some valuable lessons from the British and American studies, which focused on ultrasound along with a blood test that registered a woman's levels of a protein known as cancer antigen 125 (CA125), a proven marker for ovarian cancer.

The American test looked at levels of CA125 using a cutoff value, meaning that if a woman's blood had a level of CA125 above that value, she was considered at risk for ovarian cancer, Saslow said. But the British also took into account how rapidly the quantity of CA125 grows in a woman's bloodstream, and Saslow said that this could be key in figuring out an accurate screening test.

"Other researchers have shown that each woman has her own baseline amount of CA125," Saslow said. "What's more important are rises over time, rather than an absolute number. If my CA125 doubles or triples in a year, even if I'm under the cutoff, I should be concerned."

This is the same approach now being considered by prostate cancer researchers trying to improve the prostate-specific antigen (PSA) screening test for that type of cancer. They have found that acceleration in the amount of PSA in a man's blood should be considered as much a warning sign as a high level of the marker.

Research also continues into another promising means of screening for ovarian cancer: the use of symptoms to determine the likelihood that a woman has the cancer.

Goff said that paying attention to symptoms could be the way to a cost-effective means of screening. "Symptoms don't cost anything, and 89 percent of women with early-stage disease will have symptoms prior to their diagnosis," she said. "About 95 percent of women with late-stage disease will have symptoms prior to diagnosis."

Many of the symptoms, though, that have been associated with ovarian cancer -- bloating, abdominal pains, pelvic pain, urinary problems, difficulty eating or feeling full quickly -- are symptoms that most women feel from time to time.

"One of the problems with diagnosis of ovarian cancer is that there is no specific symptom," Goff said. "We all get bloated from time to time. We all have abdominal pain from time to time."

However, doctors now urge women to pay attention to these symptoms and be concerned if they are new and if they persist for weeks. If a woman is feeling full quickly and never has before, and the feeling doesn't go away after a few days, she should see her doctor.

"For women who have these symptoms every day for three to four weeks, there's an increased risk they have ovarian cancer," Saslow said.

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