- The Washington Times - Tuesday, May 10, 2005

Blood markers

95-percent right

REUTERS NEWS AGENCY

A test that looks at four proteins in the blood of women can show whether they have ovarian cancer, a rare and deadly cancer that is virtually impossible to screen for now, researchers said yesterday.

While their test is accurate — 95 percent versus 10 percent for the current test — they said it was still not good enough to use as a general screening test in the population.

?This test is able to differentiate healthy individuals from ovarian cancer patients with an overall sensitivity/specificity of about 95 percent,? the researchers write this week in the Proceedings of the National Academy of Sciences.

Ovarian cancer will be diagnosed in about 22,000 women this year and 80 percent of cases are not detected until the cancer has spread. That means more than 16,000 women will die of ovarian cancer this year, according to the American Cancer Society.

Currently, women are diagnosed based on vague symptoms such as bloating and abdominal pain. A protein called CA-125 is associated with ovarian cancer, but only predicts 10 percent of early-stage cases accurately.

Women diagnosed earlier have a much better chance of survival because the ovaries can be removed before the cancer has spread.

David Ward of the Nevada Cancer Institute in Las Vegas and colleagues tested 86 women for levels of 169 different proteins in their blood. Of the women, 28 were healthy and the rest had ovarian cancer.

They found four proteins that, when taken together as a group, had a similar pattern in all the women with cancer. They were leptin, prolactin, osteopontin and insulinlike growth factor-II.

?No single protein could completely distinguish the cancer group from the healthy controls,? Dr. Ward’s group stated

Tests in a larger group of women showed that if the level of all four proteins fell within a certain range, cancer was present. The test correctly diagnosed 95 percent of the women with cancer and was correct 95 percent of the time in showing a woman did not have cancer.

That is not good enough, however, for a commercial screening test, the group said, because it would incorrectly diagnose thousands of women who did not have cancer, and could miss 5 percent of those who did.

But they said it might be useful to women who know they have a high risk — for instance, women with a family history or with certain types of infertility.

?This test should improve our ability to accurately detect premalignant change or early stage ovarian cancer in asymptomatic women at increased risk for the development of ovarian cancer,? the researchers stated.

They also want to use their test to determine whether it can predict other types of cancer.

?All of the four biomarkers reported here have been suggested as potential cancer biomarkers by other research groups, although they have never been tested previously as a set.?

LOAD COMMENTS ()

 

Click to Read More

Click to Hide