Venous Thromboembolism in Surgical Lung Cancer Patients: A Provincial Population-Based Study

BACKGROUND: Venous thromboembolism (VTE) is a significant cause of morbidity and mortality in surgical patients. Thoracic surgery patients are at increased risk due to inherent technical and disease-specific factors. Other surgical specialties have adopted postdischarge extended VTE prophylaxis; however evidence is scarce in thoracic surgery. This study aims to identify VTE risk factors and associated mortality among surgical lung cancer patients. METHODS: Using administrative databases all patients in the province of Ontario undergoing lung cancer surgery from 2007 to 2017 were identified. Logistic regression identified VTE risk factors at 90 days and 1 year postoperatively. A flexible parametric survival analysis compared mortality and survival up to 5 years after surgery between patients with and without VTE. RESULTS: Of 65,513 patients diagnosed with lung cancer, 12,626 (19.3%) underwent surgery. VTE incidence at 90 days and 1 year postoperatively was 1.3% and 2.7%, respectively. Open and more extensive resections carried an increased VTE risk, with pneumonectomy conferring the highest risk (odds ratio, 2.36; P < .001). Stage III and IV disease carried a 3.19 and 4.97 times higher risk of VTE, respectively, compared with stage I (P < .001). The hazard ratio for mortality at 1 year for patients with VTE was 2.01 (P < .001). Patients suffering a VTE had reduced 5-year survival. CONCLUSIONS: Patients undergoing pneumonectomy and those with advanced stage have an increased VTE risk. Patients suffering a thrombotic complication have an increased risk of mortality and decreased 5-year survival. Accordingly strategies to reduce VTE risk should be considered in patients undergoing high-risk operations to reduce the mortality of VTEs.