Beyond C-125: Detecting ovarian cancer earlier

Successful ovarian cancer treatment often relies on catching it early. A study at MD Anderson may help point to a new method of detecting the disease for women at risk.

“Most attempts to use serum biomarkers for early detection of ovarian cancer have focused on the protein CA-125,” saidRobert Bast Jr., M.D., vice president of Translational Research. “As CA-125 is expressed by only 80 percent of ovarian cancers, multiple biomarkers will be required to detect those cancers that fail to express this antigen.”

In 1983, Bast and his colleagues published a seminal paper in the New England Journal of Medicinedetailing the protein’s discoveryand its value in helping to predict if ovarian cancer might recur.

No biomarker has been consistently elevated prior to CA-125 in prior studies. Detecting a patient’s own immune response to tumor-associated antigens might permit earlier detection, said Bast.

Bast obtained yearly blood samples from ovarian cancer patients up to seven years before diagnosis through a collaboration with Drs. Usha Menon and Ian Jacobs in the United Kingdom Collaborative Trial of Ovarian Cancer Screening.

The study examined antibodies produced by patients against the tumor gene TP53, which is mutated and overexpressed in the majority of ovarian cancers, to see if their presence would improve the ability of CA-125 to detect ovarian cancer in an earlier stage.

“Anti-TP53 autoantibodies were detected an average of 13 months prior to rising CA-125 levels and 33 months prior to diagnosis in patients who did not have a rising CA-125,” said Bast. “While only a quarter of cases are associated with anti-TP53 autoantibodies, when present, these antibodies promise to detect ovarian cancer at an earlier interval than CA-125.”

Read thefull press releasehere.