Performance of a biomarker panel to identify malignancy within a pelvic mass population
5566 Background: We previously reported the performance of biomarker combinations that displayed utility in identifying ovarian cancer from normal sera and in monitoring for disease recurrence. In this study, we evaluated the performance of a subset of these markers in differentiating ovarian cancer from benign pelvic mass. Methods: Pre-operative serum samples were prospectively collected from 254 patients undergoing surgical evaluation for differential diagnosis of a pelvic mass. Pathology showed 76 cases of epithelial ovarian carcinoma (EOC), 17 borderline tumors, 11 other gynecologic cancers, and 150 benign masses. 18 (23.7%) of the EOC patients had stage I tumors; 6 (7.9%) stage II; 44 (57.9%) stage III; and 8 (10.5%) stage IV. Serum levels of CA125, HE4, glycodelin, SLPI, MMP7, and Plau-R were ascertained. Biomarker performance was evaluated by a logistic regression model and leave one out cross-validation analysis. All calculations compared the benign vs. EOC and borderline tumor populations. Results: Individual biomarker sensitivity ranged from 28% to 77% at 85% specificity. The combination of CA125, HE4 and glycodelin exhibited the highest overall performance in identifying malignancy from benign masses, demonstrating 80% sensitivity, 80% specificity in patients <55 years, and 89% sensitivity, 80% specificity in patients ≥55. Total cohort performance was 85% sensitivity and 80% specificity. Glycodelin identified 7/22 CA125 and HE4 double negative patients, 5/7 of these patients were early stage (borderline, I or II), while only adding 4/150 false positive cases. Conclusions: Biomarker analysis within this test cohort demonstrates potential clinical utility in the differential diagnosis of pelvic mass patients, especially for the detection of early stage disease. The addition of glycodelin improved the detection of early stage cancer in sera that were negative for both HE4 and CA125. [Table: see text]