Ovarian cancer: the duplicity of CA125 measurement

Since it was first described in 1981, CA125 has held an important role in monitoring patients with ovarian cancer. CA125 is elevated in 80% of patients with epithelial ovarian cancer at initial diagnosis and correlates well with response to therapy. CA125 monitoring is used for the follow up of patients with epithelial ovarian cancer, and elevations in CA125 measurements often antedate any signs, symptoms or radiographic evidence of disease by several months. Unfortunately, data favoring early therapeutic intervention for recurrent ovarian cancer is lacking, especially in patients with isolated CA125 elevations. In asymptomatic patients, elevations in CA125 have been associated with considerable anxiety and deterioration in quality of life without any significant gains in survival. Patients with ovarian cancer should, therefore, be counseled regarding the advantages and shortcomings of intensive CA125 testing. While some patients may benefit from early detection of recurrent disease and be candidates for secondary cytoreductive surgery, others may choose to delay therapy until they develop symptoms of disease recurrence. The results of a clinical trial suggest that withholding treatment in the event of isolated rising CA125 levels will not negatively impact these patients overall survival, highlighting the need for improved salvage therapies for recurrent ovarian cancer.