Researchers may have identified an effective screening strategy for ovarian cancer that, if verified in an ongoing clinical trial, could save thousands of lives each year, according to a study published in the journal Cancer.
Currently, no established screening strategies for ovarian cancer exist, meaning the disease is often lethal as most women are only diagnosed well into the advanced stages of the disease.
In the new method tested on more than 4,000 postmenopausal women over an 11-year period, researchers from the University of Texas MD Anderson Cancer Center carried out blood tests for the protein called CA125, a known tumor marker.
Initially, all participants underwent an annual CA124 blood test. The women were then divided into groups based on a calculation called the "Risk of Ovarian Cancer Algorithm." These groups included those believed to be at low risk of developing ovarian cancer, and thus were scheduled to receive a CA125 one year later. Those of intermediate risk were scheduled to be tested in three months and, finally, those who were believed to be at high risk to receive a transvaginal ultrasound and be referred to a gynecologic oncologist.
A total of 5.8 percent of the women were determined to be of intermediate risk each year while 0.9 percent were found to be of high risk based on tests. All told, 10 women underwent surgery as a result of their ultrasound exams, four of which had invasive ovarian cancers, two had ovarian tumors of low malignant potential, one had endometrial cancer and three were benign ovarian tumors.
This translates into a positive predictive value of 40 percent for detecting invasive ovarian cancer. Meanwhile, the specificity of the testing strategy came out to 99.9 percent or, in other words, only 0.1 percent of patients without cancer would be falsely identified as having it.
Key to the study's results, as well, was the fact that all of the ovarian cancers were caught during an early stage.
"The results from our study are not practice-changing at this time; however, our findings suggest that using a longitudinal (or change over time) screening strategy may be beneficial in post-menopausal women with an average risk of developing ovarian cancer," concluded study researcher Dr. Karen Lu, a professor of gynecologic oncology.
Currently, Lu explained, she and her team are awaiting the results of a similar though larger study currently underway in the United Kingdom.
"If the results of this study are also positive, then this will result in a change in practice," she said.