OVA1 test more accurate than CA 125 in identifying ovarian cancer

May 19, 2011

Using the OVA1 blood test before surgery to assess the probability that an ovarian mass is cancerous would accurately detect ovarian cancer in more women than the currently recommended CA 125 blood test, a new study from the University of Kentucky Markey Cancer Center shows.

Using the OVA1 blood test before surgery to assess the probability that an ovarian mass is cancerous would accurately detect ovarian cancer in more women than the currently recommended CA 125 blood test, a new study from the University of Kentucky Markey Cancer Center shows.

The study, published online May 6 in Obstetrics & Gynecology, compared the performance of the American College of Obstetricians and Gynecologists’ (ACOG) ovarian tumor referral guidelines using the CA 125 test or the OVA1 test in 516 women scheduled for surgery for an ovarian mass in a diverse group of primary and specialty care centers. OVA1 accurately detected 94% of cancers in women of all ages compared with 77% found by using CA 125. Most patients in the trial didn’t show signs of advanced cancer on imaging.

OVA1 also showed improved sensitivity in premenopausal women, accurately identifying 91% of women with ovarian cancer compared with fewer than 58% identified by CA 125.

The OVA1 multivariate index assay combines the CA 125 test with 4 additional biomarkers to enhance cancer detection, especially in early stage disease. OVA1 used with the ACOG guidelines also effectively detected advanced cancer, when surgery and chemotherapy can improve overall survival.

In addition, researchers found that OVA1 decreased specificity and positive predictive value. This test is almost twice as likely as CA 125 overall to incorrectly identify women at high risk for ovarian cancer. Its possible effects on referral are uncertain and require further study, the authors note.

OVA1 is the first test approved by the US Food and Drug Administration specifically to aid in presurgical evaluation of ovarian masses for cancer. CA 125, the only previously available laboratory test, isn’t indicated for this purpose and produces variable results. OVA1 should not be used without independent clinical and radiological evaluation and is not intended for use in screening or determining whether a patient should have surgery.