Artikel der New york times von September 2012

The screenings — blood tests for a substance linked to cancer and ultrasound scans to examine the ovaries — do not lower the death rate from the disease, and they yield many false-positive results that lead to unnecessary operations with high complication rates, the panel said.

“There is no existing method of screening for ovarian cancer that is effective in reducing deaths,” said Dr. Virginia A. Moyer, the chairwoman of the expert panel, the United States Preventive Services Task Force. “In fact, a high percentage of women who undergo screening experience false-positive test results and consequently may be subjected to unnecessary harms, such as major surgery.”

The advice against testing applies only to healthy women with an average risk of ovarian cancer, not to those with suspicious symptoms or those at high risk because they carry certain genetic mutations or have a family history of the disease.

The recommendations are just the latest in a series of challenges to cancer screenings issued by the panel, which has also rejected P.S.A. screening for prostate cancer in men and routine mammograms in women under 50. The task force is a group of 16 experts, appointed by the government but independent, that makes recommendations about screening tests and other efforts to prevent disease. Its advice is based on medical evidence, not cost.

The recommendations against screening for ovarian cancer were published on Monday in Annals of Internal Medicine. But the warning is not new; the panel is reaffirming its own earlier advice.

Although the task force has sometimes drawn fire in the past, particularly with its stand on mammograms, it has plenty of support in this case. Other medical groups, including the American Cancer Society and the American Congress of Obstetricians and Gynecologists, have for years been discouraging tests to screen for ovarian cancer.

But some doctors continue to recommend screening anyway, and patients request it, clinging to the mistaken belief that the tests can somehow find the disease early enough to save lives. A report published in February in Annals of Internal Medicine, based on a survey of 1,088 doctors, said that about a third of them believed the screening was effective and that many routinely offered it to patients.

“We are fueled by hope,” Dr. Moyer said. “It’s such a terrible disease. Almost everyone knows somebody’s who’s had it, and that means somebody who’s died of it. You get the feeling you should do anything possible to avoid that situation, but it’s easy to forget that what you do to avoid it can make matters worse.”

Ovarian cancer is among the more rapidly fatal forms of cancer. This year, 22,280 new cases and 15,500 deaths are expected in the United States, according to the American Cancer Society.

In most cases, ovarian cancer is already advanced by the time it is diagnosed. Doctors say the only advice they can give women is not to ignore symptoms that may be the first warning of the disease: persistent bloating, pelvic or abdominal pain, feeling full early while eating and needing to urinate frequently.

For its latest recommendations, the panel relied heavily on a large study published last year in The Journal of the American American Medical Association of 78,216 women ages 55 to 74. Half were screened and half were not, and they were followed for 11 to 13 years. The screening consisted of ultrasound exams and blood tests for elevated levels of a substance called CA-125, which can be a sign of ovarian cancer.

There was no advantage to screening: the death rate from ovarian cancer was the same in the two groups.

But among the women who were screened, nearly 10 percent — 3,285 women — had false-positive results. Of those women, 1,080 had surgery, usually to remove one or both ovaries. Only after the operations were done was it clear that they had been unnecessary. And at least 15 percent of the women who had surgery had at least one serious complication, like blood clots, infections or surgical injuries to other organs.

To find one case of ovarian cancer, 20 women had to undergo surgery.

The problem with the tests is that CA-125 can be elevated by conditions other than cancer, and ultrasound can reveal ovarian enlargement or cysts that are benign but that cannot be distinguished from cancer without surgery to take out the ovary.

Nan Gudgell, 70, of Bountiful, Utah, participated in the large study. She was hoping to be in the half that were screened, so she was a bit disappointed to find that she was not. “You hope you’re going to get it and your life is going to be saved,” she said.

But upon hearing the results, Mrs. Gudgell said, “Maybe I’m the lucky guy.”

Dr. Saundra S. Buys, an author of the study and a professor of medicine at the Huntsman Cancer Institute at the University of Utah, said that despite the bad news about screening, “I think it is still being done. I think some doctors and a lot of patients really do get enticed by the possibility that they’ll find a disease early, that it might save their lives.”

Dr. Barbara A. Goff, a gynecologic oncologist at the Fred Hutchinson Cancer Research Center in Seattle and an author of the study last year that found doctors still in favor of screening, said: “If patients request it, then I think a lot of times physicians feel it’s just easier to order the test, particularly if it’s covered by insurance, rather than taking the time to explain why it may not be good, that it could lead to inappropriate surgery, could lead to harm. I don’t think they think through the consequences.”

Dr. Edward E. Partridge, the director of the cancer center at the University of Alabama, Birmingham, and another author of the large study that found screening ineffective, said that even if the testing could be improved to reduce false-positive results, it still would not save women’s lives. Even if false positives could be eliminated, the death rate from the cancer would be the same whether women were screened or not, suggesting that the test simply cannot find the cancer early enough to make a difference.

“You can fine-tune it all you want to, and that still doesn’t change the bottom line,” Dr. Partridge said, adding that he also thought many doctors were still recommending the tests despite the data. “I think it’s really important that both the physician and the public really learn and assimilate that this test as it’s currently delivered is not effective at reducing death rates from ovarian cancer. We’ve got to find something else.”

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