"Most attempts to detect early ovarian cancer with serum biomarkers focus on CA125," said Dr. Robert bast Jr., vice president of transformation research. "Because only 80% of ovarian cancer expresses CA125, multiple biomarkers are necessary for those patients who do not express this antigen. "

In the previous study, no biomarker was found to be higher than CA125. Testing a patient's own immune response to tumor-related antigens may help detect early ovarian cancer, bast said.

In collaboration with usha Menon and Ian Jacobs, Ph.D., who are responsible for ovarian screening collaboration trials from the UK, bast receives blood samples from ovarian cancer patients every year, some even seven years before diagnosis.

TP53 is mutated and overexpressed in most ovarian cancers. This study examined the antibodies produced by the patient's anti-tumor gene TP53 to see whether the antibody is expressed in a more early stage, so as to improve CA125's ability to detect ovarian cancer.

"TP53 antibody was detected 13 months earlier than CA125 on average, and 33 months earlier than the diagnosis of ovarian cancer without CA125 elevation. "Bast said. "Although only a quarter of cases are associated with TP53 autoantibodies, ovarian cancer can be diagnosed earlier than CA125 as long as such antibodies are present. "

These data were reported at the 2015 AACR annual meeting in Philadelphia on April 20.