Ovarian Cancer Blood Test in Development
3 Proteins Stand Out in Patients' Blood
Aug. 15, 2004 -- A blood test is in the works to detect ovarian cancer at its earliest stages. The test, developed by researchers at Johns Hopkins Kimmel Cancer Center, focuses on three proteins that are found in the blood of women with the disease.
"Early detection remains the most promising approach to improve long-term survival of patients with ovarian cancer," write the researchers in the Aug. 15 issue of Cancer Research.
Every year in the U.S., 23,000 women are diagnosed with ovarian cancer and 14,000 die of it. The disease is known for spreading quickly and being hard to detect.
Poor survival rates from ovarian cancer are often attributed to the fact that it is a silent cancer --symptoms appear only late in the disease. Survival from the cancer depends on early diagnosis of the disease.
Scientists led by Johns Hopkins associate pathology professor Zhen Zhang, PhD, analyzed 195 blood samples from ovarian cancer patients, healthy women, and women with benign pelvic tumors.
Three proteins stood out as potential markers for ovarian cancer. One was found in increased levels in women with ovarian cancer. The other two proteins were found at lower levels in women with ovarian cancer.
Researchers also tracked a blood marker called CA125 in the women. "Combining CA125 with our new markers may improve early detection capabilities," says Zhang in a news release.
Of 23 women with early-stage ovarian cancer, the three blood proteins plus CA125 correctly identified ovarian cancer 74% of the time, compared with 65% for CA125 alone.
The researchers tried to improve the test's accuracy by lowering the threshold of CA125 at which ovarian cancer would be suspected. With that adjustment, the test correctly identified ovarian cancer 83% of the time.
More Work Needed
The blood test won't be available until further studies are done on larger groups of patients. The researchers also caution that it's not likely to always catch every cancerous ovarian tumor.
"The goal is to come as close as possible to that by using this test in combination with other available diagnostic goals," says Daniel Chan, PhD, professor and director of the Biomarker Discovery Center at Johns Hopkins, in a news release.