Serum fibrinogen is an independent prognostic factor in operable nonsmall cell lung cancer

Serum fibrinogen converted to insoluble fibrin by activated thrombin, plays an important role in the coagulation system. Increased fibrinogen considerably influences cancer cell growth, progression and metastasis. In nonsmall cell lung cancer (NSCLC), however, the association between serum fibrinogen concentration and prognosis has not been fully examined. We enlisted 567 operable NSCLC patients in our study. Preoperative serum fibrinogen was measured by the Clauss method. The association of serum fibrinogen concentration with clinical pathological factors and patient outcome was evaluated. Survival analysis indicated that serum fibrinogen was an independent prognostic factor in operable NSCLC. Patients with hyperfibrinogenemia had an elevated risk of disease progression and death compared to patients with normal fibrinogen levels. The hazard ratio was 1.49 (95% confidence interval [CI] 1.07-2.05) for disease progression and 1.64 (95% CI 1.06-2.53) for death. The trend linking increasing fibrinogen levels with risk was also statistically significant for both outcomes (p < 0.05). These analyses were adjusted for patient age, sex, smoking behavior, disease stage, tumor grade and histology. Kaplan-Meier survival curves showed similar results. Preoperative serum fibrinogen is a novel independent prognostic biomarker in operable NSCLC.