Not only is there still not a reliable routine test for ovarian cancer, the existing options may do more harm than good, according to a major government health panel.
The new U.S. Preventive Services Task Force recommendation, issued Monday, reaffirms its 2004 stance on ovarian cancer screening and highlights the lack of effective early detection options for women.
"Screening for ovarian cancer is not a good use of a patient's or a doctor's time or resources," Dr. Virginia Moyer, a member of the task force, told The Huffington Post. "It does not improve mortality, and no major organization recommends it."
In 2012, more than 22,000 women in the U.S. will receive a new diagnosis for ovarian cancer, according to the American Cancer Society. The disease is relatively uncommon -- a woman's risk of developing ovarian cancer during her lifetime is about 1 in 71 -- but it is dangerous. In the U.S., it is the fifth-leading cause of cancer death in women, behind cancer of the lung, breast, colon and rectum and pancreas.
"Ovarian cancer is worth screening for because it is very deadly," said Dr. Stephanie Blank, an OB-GYN and associate professor with the NYU Langone Medical Center. Blank said outcomes would be improved if doctors could detect the disease earlier. However, the current screening methods are problematic, in part because they often lead to false positives, Blank explained.
In devising the new recommendations, the task force reviewed recent studies looking at the efficacy of the two most common tests used to screen for ovarian cancer: transvaginal ultrasound and the CA-125 blood test. The former, in which an ultrasound is used to look for masses in the ovaries, had generally been thought to be the more promising method for screening. The CA-125 test is used to check for levels of that protein in the blood, which are higher in women with ovarian cancer.
But neither reduces the number of deaths from ovarian cancer, the new USPSTF recommendation states, and there is "at least moderate certainty" that the harms outweigh the benefits.
It points to several studies that have found potential harms, such as false positives that have lead to major surgery, including removal of a woman's ovary. One study found that, on average, for every one case of ovarian cancer detected, 33 women had surgery for a false positive.
Results from the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial that began enrollment in 1993 and closed enrollment in 2001, involving more than 78,000 women, found that neither CA-125 or transvaginal ultrosonography reduced ovarian cancer mortality.
Neither the American Congress of Obstetricians and Gynecologists nor the American Cancer Society, nor most other major medical organizations, recommend routine screening healthy women for ovarian cancer.
Despite this, a survey conducted last February found that one in three physicians believed ovarian cancer screening is effective and many reported offering screening for low-risk women.
"Sometimes physicians are enthusiastic about cancer screening before the [scientific] evidence shows that the benefits outweigh the risks," Dr. Laura-Mae Baldwin, an investigator on that study and a professor of family medicine with the University of Washington, said in a statement.
"It's a killer disease. It would be really great to have a test," Blank said, but there are roadblocks. One is that there are not many "precursors" to the disease that are easy to detect with a screening test, she said. For example, pap smears can be used to detect abnormal cervical cells that can develop into cervical cancer if untreated. As yet, doctors have no reliable way to look for abnormal ovarian cells that could turn cancerous. Ovarian cancer has sometimes been called the "silent killer" because it often goes undetected until the disease has progressed to a relatively advanced stage. Only 15 percent of patients with the disease are diagnosed early, when their chances of survival are highest.
Another difficulty in catching ovarian cancer early is that its symptoms aren't specific to the disease. They include constipation, bloating, loss of appetite or feeling full more quickly after a meal and changes in urinary frequency.
Women with a family history of ovarian cancer have an increased risk of developing it, as do older women and women with inherited breast cancer genes or so-called "BRCA" mutations. The new USPSTF recommendations are for women with average risk -- women with BRCA mutations should talk to their doctors about surveillance options.
Overall, experts say the findings highlight the pressing need for better screening and diagnostic tools for ovarian cancer, which has a lower relative five-year survival rate (46 percent) than cervical cancer (70 percent) and breast cancer (89 percent).
"Researchers need to keep working on finding a way to either prevent or diagnose this terrible disease very early," Moyer, of the USPSTF, said.