[Analysis of the Incidence of Lower Extremity Venous Thrombosis and Its Related Risk Factors in Admitted Patients with Lung Cancer].

BACKGROUND: Venous thromboembolism (VTE) is a recognized complication in lung cancer patients with higher morbidity and mortality. The purpose of this study is to determine the incidence of lower extremity venous thrombosis (LEDVT) in lung cancer patients and to reveal the risk factors for LEDVT during admission in our center.

METHODS: We first connected 231 patients with lung cancer admitted to the Department of Lung Cancer Surgery, Tianjin Medical University General Hospital from July 2017 to December 2017. All these patients underwent color ultrasound examination of lower extremity vein on admission to analyze the incidence of LEDVT. At the same time, the incidence of LEDVT in patients with benign lung diseases on admission was used as control. In order to explore the possible risk factors for LEDVT in these patients with lung cancer, we further analyze the correlations between LEDVT and their clinical features. At the same time, we also analyze the relationship between LEDVT and Plasma D-Dimmer, fibrinogen (FIB), thrombin time (TT), activated partial thrombin time (APTT), prothrombin time (PT) and platelet (PLT) in these patients with lung cancer.

RESULTS: Among 231 patients with lung cancer, the incidence rate of LEDVT on admission was 5.2% (12/231), and in 77 patients with benign lung disease, there was none of patients with LEDVT on admission. This result indicated that the admitted incidence rate of LEDVT in patients with lung cancer was significantly higher than that in patients with benign lung disease (P<0.05). Further analysis in patients with lung cancer found that there was higher incidence rate of LEDVT in distant metastasis group (including N3 lymph node metastasis) compared to in non-distant metastasis group (11.29%, 7/62 vs 2.96%, 5/169) (P<0.05). In patients with lung cancer, the median value of D-Dimer in LEDVT group was 1,534 mg/L (369 mg/L-10,000 mg/L), which was significantly higher than that in the non-LEDVT group (539 mg/L, 126 mg/L-1,000 mg/L) (P<0.05). There was no statistically significant difference in FIB, TT, APTT, PT and PLT between these two groups (P>0.05).

CONCLUSIONS: The overall incidence of LEDVT in our central lung cancer patients was approximately 5%, significantly higher than that in patients with benign lung disease. Lung cancer patients with distant metastasis (including N3 lymph node metastasis) at admission were more likely to develop LEDVT, and these patients with higher D-Dimer values should be considered the possibility of VTE events.