USC researchers develop blood test to screen for early-stage ovarian cancer

A new blood test may help clinicians screen patients for the most common and lethal type of ovarian cancer—high-grade serous ovarian carcinoma, or HGSOC—and help inform the best course of treatment.

Researchers at the University of Southern California (USC) have developed a blood test that can determine whether a pelvic mass is benign or cancerous—an intervention that can eliminate the need for surgery if biopsy isn’t possible. The test, dubbed OvaPrint, may be more reliable than existing tests for HGSOC when it’s early in its growth and easiest to treat, according to the study published on October 9.

“The test has the potential to improve treatment, because the surgical approach to removing a pelvic mass differs depending on whether it’s benign or not,” Bodour Salhia, the study’s coauthor and coleader of the USC Norris Comprehensive Cancer Center’s genomic and epigenomic regulation research program, said in a statement. “Right now, doctors essentially have to take their best guess.”

As part of the study, USC researchers analyzed more than 370 tissue and blood samples from patients with early-stage HGSOC, benign tumors, or “normal” ovaries. They found that healthy and HGSOC tissue had varying patterns of DNA methylation—a process that alters the way the body expresses genes and can signal certain diseases, and is also a HGSOC biomarker.

The OvaPrint test looks for DNA fragments with these early molecular changes in a patient’s blood. In the study, the test had a 91% accuracy rate, according to the researchers.

While a transvaginal ultrasound or a CA-125 blood test, which measures the amount of cancer antigen 125 protein in the body, can help diagnose the disease, there is no reliable screening test that detects early-stage ovarian cancer, according to UCLA Health.

The American Cancer Society estimates that in 2023, almost 20,000 patients will be diagnosed with ovarian cancer, and more than 13,000 will die from the disease. If the cancer is detected early, patients have an over 90% chance of living for five or more years, but those chances can drop to 40% if the cancer is found in its later stages, according to the USC researchers.

Salhia founded biotech company CpG Diagnostics to bring the OvaPrint tests to market. The researchers said they are planning another study to confirm their initial findings, and depending on those results, they hope to make OvaPrint commercially available for clinical use in the next two years.

OvaPrint may also have the potential to detect other subtypes of ovarian cancer or be used as a general screening tool to test for the disease in asymptomatic patients, according to the researchers.

“Early detection saves lives,” Salhia said in a statement. “If we can accurately identify early-stage ovarian cancer, we can change the outcome of the disease and really crank up survival rates.”