Diagnostic accuracy of serum insulin-like growth factor-binding protein 2 for ovarian cancer

Introduction Insulin-like growth factor-binding protein 2 (IGFBP2) plays an important role in the pathogenesis of ovarian cancer. The most prominent effects of IGFBP2 include promoting proliferation, driving invasion, and suppressing apoptosis. This study aimed to determine the diagnostic accuracy of serum IGFBP2 in differentiating between benign and malignant ovarian neoplasms. Methods Preoperative serum IGFBP2 level was evaluated from 76 women with primary ovarian tumor who underwent exploratory laparotomy at Sanglah General Hospital, Denpasar, Bali, Indonesia. The optimal threshold value of IGFBP2 for the diagnosis of ovarian cancer was determined from the receiver 0perating characteristic (ROC) curve. The diagnosis was confirmed by histopathologic analysis of resected ovarian specimens. Results Forty-six (60.5%) patients were diagnosed with ovarian cancer. The area under the ROC curve (AUC) of IGFBP2 in detecting ovarian cancer was 0.815 (95% CI: 0.721 to 0.910, P<0.001). For a given specificity larger than 95%, the optimal sensitivity was 63%. The optimal threshold value of IGFBP2 for the diagnosis of ovarian cancer was 804 ng/mL [sensitivity 63%, specificity 96.7%, positive predictive value (PPV) 96.7%, negative predictive value (NPV) 63%, accuracy 76.3%, and diagnostic odd ratio (DOR) 49.5 (95% CI 6.1 to 396.5)]. In a subgroup analysis, IGFBP2 showed excellence performance in diagnosing advanced ovarian cancer (AUC 0.904 [95% CI: 0.806 to 1.000], sensitivity 83.3%, specificity 96.7%, PPV 95.2%, NPV 87.9%, accuracy 90.7%, and DOR 145.0 [95% CI 15.0 to 1395.3]). Conclusion IGFBP2 is a novel and potentially promising biomarker for detecting ovarian cancer. Further studies are needed to confirm its diagnostic performance in premenopausal women and for detecting early stage ovarian cancer.