[Platelet activation in lung cancer]. / Activation plaquettaire dans le cancer du poumon.

During primary hemostasis the platelets aggregate to form the platelet thrombus. ADP and thrombin generated by coagulation are the main agonists in platelet aggregation. In a previous study we were able to show that patients with lung cancer had hypercoagulability, hyperfibrinogemia (≥ 6.22 g/L) was predictive of thromboembolic disease at the start of diagnosis before any therapy. In this study, we studied platelet aggregation in these patients in order to demonstrate whether they have hyperaggregability associated with the hypercoagulability demonstrated previously, and this by evaluating abnormalities in primary hemostasis (platelet count and platelet aggregation). One hundred and one patients diagnosed before any therapy and 72 blood donors were included. Agonists used for platelet aggregation are collagen and adenosine diphosphate at low concentrations. Hyperaggregability is observed when blood platelets are stimulated by ADP at different concentrations (p ≤ 0.01). This hyperaggregability is influenced by the histological type and not the development of the cancer, the age of the subjects and the platelet count, it is independent of hyperfibrinogemia and the occurrence of thromboembolic disease. However, an increase in the platelet level is found in patients with hyperfibrinogemia. Patients with lung cancer present platelet activation observed by aggregometry in response to ADP; which is not influenced by hyperfibrinogemia during cancer.

[Activation of coagulation in patients with lung cancer]. / Activation de la coagulation chez des patients atteints du cancer du poumon.

The aim of this study is to evaluate the anomalies of coagulation (by assaying the factor VIII, fibrinogen, D-dimer and resistance to activated protein C) in patients with lung cancer. METHODS: 101 patients newly diagnosed with lung cancer before treatment and 72 control blood donors were included in the study after informed consent. All coagulation tests were performed on Stago STA-Compact. Statistical analyses were performed using the SPSS software version 22. RESULTS: The study of the coagulation showed that plasma levels of all coagulation parameters were significantly higher in patients compared to controls. Coagulation was not influenced by the age of patients. No significant difference was found between the histological types in terms of coagulation. Factor VIII level was significantly elevated in stage IV patients compared to stage I + II + III patients. At the cut-off value of 6.22 g/L, the elevation of fibrinogen had a significant statistical relationship with thromboembolic disease (p=0.014) giving an hazard ratio of 3.868, confidence interval [1.358-11.012]. In multivariate analysis the hazard ratio doubled to 6.398, confidence interval [1,970-20,778]. DISCUSSION: Lung cancer patients showed an increase in coagulation factors that resulted in a state of hypercoagulability that was independent of the histology of lung cancer. The elevation of fibrinogen was predictive of thromboembolic disease at the early diagnosis of lung cancer before any therapy.