A double-whammy method of screening for ovarian cancer, which is sometimes called the silent killer, seems to catch many cases in the early stages when the disease is more curable, researchers say. A massive study tested the impact of two types of screening: One is a blood test which measures the levels of a protein called CA125, which is often higher in women with ovarian cancer. The other is an ultrasound scan that looks for abnormalities in the ovaries [The Guardian]. When used in conjunction, the two tests showed great promise in catching cancer cases early on.
Ovarian cancer is one of the most lethal types of cancer. About 21,000 U.S. women are diagnosed each year and more than 15,000 die. The high death rate is due to the fact that the disease is often detected at a late stage of development, when chances for a cure are much lower [Los Angeles Times].
However, many of the women in the study had false positive results, especially those who received only an ultrasound test, leading some to unnecessarily have their ovaries removed. Lead researcher Ian Jacobs cautioned that “women thinking of having [an ultrasound screening] must understand and realize that there’s a possibility it will do more harm than good. We have reason to think it will save lives,” he added, “and then the question is, will it save enough lives to balance out the harm it does?”[The New York Times].
The broad study, published in The Lancet Oncology, involved more than 200,000 post-menopausal women. About half received no screening, and the remaining women were divided into a group that just received annual ultrasounds and a group that received blood tests followed by ultrasounds if indicated. Among women who took both tests, researchers caught 90 percent of ovarian cancer cases, while ultrasound alone caught 75 percent. Most encouragingly, almost half of all the cancers detected were in early stages and hadn’t spread far, increasing the chance that those patients could be cured.
The study is expected to continue until at least 2014, and researchers ask the public to be patient as they wait for the trial’s full results. Jacobs also notes that the study has not yet shown that screening reduces the death rate from ovarian cancer. “It needs to be seen in the context of what is a 25-year research programme…. It started in the mid-1980s and will finish in 2015. It’s a massive, massive effort but all of the results we have got are lining up in the right direction. What we need to show everybody is not only that this screening programme can pick up the cancer early, but also that we are saving lives” [The Guardian], says Jacobs.
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