
USC Researchers Develop New Accurate Blood Test for Assessing Ovarian Cancer in Patients With Adnexal Masses
A research team at the USC Norris Comprehensive Cancer Center has unveiled data on a new blood test that exhibits high accuracy in distinguishing between benign and cancerous pelvic masses. Ovarian cancer, particularly the high-grade serous subtype (HGSOC), has posed a significant challenge for early-stage diagnosis and effective treatment. This form of ovarian cancer is both the most prevalent and lethal, primarily because of the lack of efficient screening methods. One of the primary diagnostic dilemmas in managing ovarian cancer is the difficulty in distinguishing between benign and cancerous pelvic masses before surgery. Conventional biopsies are often not a feasible option. Hence, clinicians often have to make crucial treatment decisions based on incomplete information. Approximately 5% to 10% of all women will develop adnexal masses in their lifetime.
The researchers at USC Norris Comprehensive Cancer Center have pioneered a liquid biopsy called OvaPrint, designed to identify specific nucleic acids circulating in the blood. OvaPrint employs a cell-free DNA methylation liquid biopsy approach. This technique searches for circulating DNA in the blood that exhibits specific methylation patterns at certain nucleic acids. Methylation represents a complex modification of DNA in cells, impacting gene expression and serving as a biological marker of disease. The OvaPrint test has been designed to identify HGSOC when it is in its early stages.
The test has demonstrated the potential to determine the malignancy of pelvic masses with 91% diagnostic accuracy rate, surpassing existing tests available in the market. In this study, a comprehensive analysis was conducted on a dataset comprising 372 samples, with 59 from tissue samples and 313 from plasma samples. The findings revealed that OvaPrint exhibited a positive predictive value of 95% and a negative predictive value of 88% when distinguishing between high-grade serous ovarian carcinoma (HGSOC) and benign masses. However, data on cancer diagnostics is often higher in studies using documented controls compared to real world testing. The test could aid in streamlining the treatment process for patients with pelvic masses offering clinical insights into the nature of the mass, which, in turn, can guide treatment strategies. This information can help healthcare providers make informed decisions on the choice of surgery. Currently in the U.S. there are about nine surgeries for every detected malignancy.
Other commercial tests are on the market for detecting ovarian cancer, most notably Ova1 which is offered by Aspira Women’s Health and measures five protein biomarkers in blood. The test has diagnostic accuracy of 79.2% in clinical studies.
Moreover, the OvaPrintTM test may also extend its utility beyond the patient with a known pelvic mass. The researchers are currently exploring its potential application as a screening tool for asymptomatic women in the general population, aiming to detect early-stage ovarian cancer when it is most treatable. The researchers aim to introduce a commercially viable version of OvaPrintTM for clinical use within two years. The researchers are also exploring potential modifications to extend the test’s application to other subtypes of ovarian cancer, ultimately striving to create a tool for broad population screening.