Lobectomy and postoperative thromboprophylaxis with enoxaparin improve blood hypercoagulability in patients with localized primary lung adenocarcinoma.

BACKGROUND: Patients with lung adenocarcinoma undergoing surgery are in high risk for VTE and receive routine post-operative thromboprophylaxis with LWMH. AIM: We investigated markers of hypercoagulability in patients with primary localized adenocarcinoma and the modifications induced by lobectomy and postoperative administration of enoxaparin.
MATERIALS AND METHODS: Patients suffering from localised primary lung adenocarcinoma (n=15) scheduled for lobectomy were studied. The control group consisted of 15 healthy age and sex-matched individuals. Blood was collected before anaesthesia induction and after surgery, at several intervals until the 7th post-operative day. Samples were assessed for thrombin generation, phosphatidylserin expressing platelet derived microparticles expressing (Pd-MP/PS(+)), tissue factor activity (TFa), FVIIa and TFPI levels, procoagulant phospholipid dependent clotting time and anti-Xa activity.
RESULTS: At baseline, patients showed increased thrombin generation and Pd-MP/PS(+). After lobectomy thrombin generation significantly decreased. Administration of enoxaparin attenuated thrombin generation. In about 50% of samples collected post-operatively an increase of thrombin generation occurred despite the presence of the expected anti-Xa activity in plasma. At the 7th post-operative day, 3 out of 15 patients showed a significant increase of thrombin generation.
CONCLUSION: In patients with localized lung adenocarcinoma, hypercoagulability is characterized by high thrombin generation and increased concentration of Pd-MP/PS(+). Tumor mass resection is related with attenuation of thrombin generation, which is inhibited by postoperative thromboprophylaxis with enoxaparin. The response to enoxaparin is not predicted by the concentration of the anti-Xa activity in plasma. The assessment of thrombin generation during prophylaxis with enoxaparin allows to identify patients with high residual plasma hypercoagulability.