Aims: An elevated plasma D-dimer level indicates the activation of coagulation and fibrinolysis. In the present study, we investigated the association of pre-treatment haemostatic parameters (D-dimer, fibrinogen and prothrombin fragment 1+2) with clinicopathological parameters and outcome in patients with lung cancer.
Materials and methods: Plasma levels of D-dimer and other parameters were measured in 78 evaluable patients with lung cancer (60 non-small cell lung cancers, 18 small cell lung cancers). At diagnosis, 35 patients (44.9%) were locally advanced stage (IIIA/B) and 43 patients (55.1%) had metastatic disease (IV). Multivariate statistical analysis was carried out using Cox's proportional hazards model. The receiver operating characteristic curve was used to determine the cut-off values for D-dimer, fibrinogen and prothrombin fragment 1+2.
Results: The median survival for all patients was 264 days (95% confidence interval 200-328 days). A significant association between the plasma levels of D-dimer and the response to chemotherapy was observed (P=0.03). With the univariate analysis, tumour stage, pre-treatment plasma levels of D-dimer, fibrinogen, platelet count, lactate dehydrogenase concentration and Karnofsky performance status were predictive for survival. With the multivariate analysis (P< or =0.1), the plasma level of D-dimer (P<0.001), tumour stage (P=0.01) and Karnofsky performance status (P=0.02) were identified as independent predictive factors. The median survival times were 405 days (95% confidence interval 165-644 days) and 207 days (95% confidence interval 146-267 days, P<0.001), respectively, for patients with a low D-dimer level (< or =0.65 microg/ml) and a high D-dimer level (>0.65 microg/ml).
Conclusions: Elevated plasma levels of D-dimer in patients with lung cancer are associated with decreased survival and a poor response to treatment. Pre-treatment for the D-dimer level may be useful in the prediction of survival and the response to treatment.