Serum thrombomodulin as a metastatic and prognostic marker in soft tissue sarcomas.

Background: Thrombomodulin (TM) has multiple biological functions and modulates not only anti-coagulation, but also cell proliferation, adhesion, and anti-inflammation activities. The main function of TM is to activate the anticoagulant pathway of protein C. Soluble TM is related to metastasis by its inactivation of thrombin.

Objectives: To clarify the correlation between serum TM levels and clinicopathological parameters.

Methods: The plasma TM levels (FU/ml) of 135 primary soft tissue tumors (benign, 67; soft tissue sarcoma (STS), 68) were measured before biopsy or treatment. TM levels were analyzed and compared to various clinicopathological parameters. Log-rank test and Cox proportional analysis were used to evaluate recurrence-free survival, metastasis-free survival, and overall survival.

Results: STS tumors had significantly higher TM values (15.9) than benign tumors (13.7) (p= 0.0138). 5-year MFS was 81.1% in low TM and 40.0% in high TM (p= 0.00671), and 5-year OS was 85.5% in low and 52.5% in high TM in grades 1-3 (p= 0.0673). In multivariate COX proportional analysis, high-TM showed a significant difference (MFS: HR 4.37, p= 0.0147; OS: HR 3.60, p= 0.0557) in grades 1-3.

Conclusions: We demonstrated that a high level of soluble TM has the potential to be a significant predictor of metastasis and poor prognosis in STS patients. TM is a candidate molecular marker for high metastatic potential and can be clinically useful for guiding therapeutic strategy.