Beyond CA125: the coming of age of ovarian cancer biomarkers

Ovarian cancer is the fourth leading cause of cancer deaths among women in the USA, despite its relatively low incidence of 50 per 100,000 women. Even though advances in therapy have been made, the ovarian cancer fatality-to-case ratio remains exceedingly high, owing to the lack of accurate tools to diagnose early-stage disease when cure is still possible. The most studied marker for ovarian cancer, CA125, is only expressed by 50-60% of patients with early-stage disease. Major efforts have been deployed to identify novel serum markers, yet no single marker has emerged as a serious competitor for CA125. Various groups are investing in combination approaches to increase the diagnostic value of existing markers, but many markers may still lie in underexplored areas of ovarian cancer biology, such as tumor vasculature environment and post-translational modifications (glycomics).