Abstract: Provided are methods for diagnosing ovarian cancer or assessing the risk of developing ovarian cancer in a subject by measuring, in a biological sample from the subject, the amount of IL-6 and comparing the amount of IL-6 measured to a predetermined IL-6 cutoff value. Also provided are methods that further include measuring, in the biological sample, the amount of two or more biomarkers selected from the group consisting of transthyretin, apolipoprotein A1, transferrin, ?-2 microglobulin, and CA 125 II. The amount of IL-6 and biomarkers are useful in the diagnosis of ovarian cancer, and individuals can be identified as having ovarian cancer when the amount of IL-6 is greater than the IL-6 cutoff value and/or the biomarker score is greater than the biomarker score cutoff value.