Tissue factor pathway inhibitor 2 as a serum marker for diagnosing asymptomatic venous thromboembolism in patients with epithelial ovarian cancer and positive D‑dimer results

Tissue factor pathway inhibitor 2 (TFPI2) is a serodiagnostic marker for epithelial ovarian cancer (EOC) and is the primary inhibitor of the extrinsic coagulation pathway. The present study assessed the diagnostic performance of TFPI2 for detecting venous thromboembolism (VTE) in patients with EOC and positive D-dimer results (>1.0 µg/ml). First, the clinical data of 81 patients with EOC admitted to Nara Medical University Hospital between January 2008 and December 2015 were collected. Also, 25 patients with VTE and 56 patients without VTE were included. Receiver-operating characteristic (ROC) curve analyses were performed to determine the diagnostic efficacy of TFPI2 in discriminating patients with VTE from those without VTE. Serum TFPI2 levels in patients with VTE were significantly higher than in non-VTE patients (median, 472.2 vs. 279.1 pg/ml, P<0.001). Using the Youden index, the optimal cutoff value for the TFPI2 level was set at 398.9 pg/ml. Furthermore, the sensitivity, specificity, positive predictive value and negative predictive value of TFPI2 for diagnosing VTE were 64.0, 80.4, 59.3 and 83.3%, respectively. Additionally, 80.4% of patients with TFPI2 levels <398.9 pg/ml were VTE-negative. ROC analysis demonstrated that the area under the curve for TFPI2 was 0.729 (95% confidence interval, 0.614-0.844). Conclusively, TFPI2 may distinguish patients with VTE from those without VTE among patients with EOC and positive D-dimer results.