New screening method detects ovarian cancer in twice as many women
Researchers have developed a new ovarian cancer screening technique that they say can detect ovarian cancer in twice as many women as traditional methods. The study was recently published in the Journal of Clinical Oncology.
Ovarian cancer is one of the most deadly types of cancer because it is usually detected then the cancer has developed into an advanced stage. The disease ranks fifth in cancer deaths among women. There are about 250,000 women diagnosed each year and about 140,000 deaths from ovarian cancer each year. A woman’s risk of getting this type of cancer is about 1 in 73 and her risk of dying from it is about 1 in 100.
Women at Risk for Ovarian Cancer
All women are at risk for ovarian cancer. It mainly develops in older women – about half of the women diagnosed are 63 years or older. It is more common in Caucasian women than African-American women. Women are most often diagnosed between the ages of 40 and 70, and even more so in women between the ages of 50 and 59. However, it does occur in younger women too. When younger individuals are diagnosed with cancer, it is often more aggressive.
The study results from the UK Collaborative Trial of Ovarian Cancer Screening - the largest ovarian cancer screening trial in the world - could mean a new way to detect many more cases of ovarian cancer and even more importantly, early enough to spare many women’s lives from this deadly disease.
The study was conducted by the University College London. Researchers specifically looked at the blood protein, CA125. CA125 is a tumor marker or biomarker which is a substance that is found in greater concentration in tumor cells than in other cells of the body. CA 125 has a strong presence in ovarian cancer cells than in other cells, and is often tested in women who have a higher risk for ovarian cancer.
For the trial, the researchers used a new algorithm to evaluate the levels of CA125. The study included 202,638 post-menopausal women who were aged 50 and over. All the participants were randomly assigned to receive either annual multimodal screening, trans-vaginal ultrasound or no test at all.
The researchers followed up with 46,237 of the women who continued to receive annual multimodal screening who all had their CA125 levels tested annually for 14 years. Using the new algorithm, the researchers calculated their risk of ovarian cancer using their age, their initial CA125 levels, and any changes in their CA125 levels that occurred over time. They then estimated their risk for ovarian cancer by comparing the serial pattern with known cases of cancer and controls.
Among the women who received multimodal screening, 640 of them had surgery for suspected ovarian cancer. Of these 640, 133 had invasive epithelial ovarian cancers. And another 22 women were diagnosed with epithelial ovarian cancer within one year of their final annual screen. The researchers will not receive the results regarding the impact of screening on ovarian cancer deaths until later in the year.
"The numbers of unnecessary operations and complications were within acceptable limits," states Prof. Menon. "While this is a significant achievement, we need to wait until later this year when the final analysis of the trial is completed to know whether the cancers detected through screening were caught early enough to save lives."
New Treatment for Ovarian Cancer
Testing for CA 125 is not a new method to test for ovarian cancer. However, the researchers did use a new statistical calculation method called ROCA algorithm. Incorporating this method allowed the researchers to detect ovarian cancer in 86 percent of women, compared to detecting it in between 41 and 46 percent of women using the standard screening method.
Currently, there is no nationally recognized screening method to detect ovarian cancer because there has not been sufficient enough research or evidence to suggest a method that would improve rates of early tumor detection. "These results are therefore very encouraging," says trial coordinator Professor Usha Menon. "They show that use of an early detection strategy based on an individual's CA125 profile significantly improved cancer detection compared to what we've seen in previous screening trials."
A blood test to identify women at risk for ovarian cancer is exciting. However, this potential screening method still needs to be tested on more women to determine its effectiveness in detecting ovarian cancer early and saving lives.