Predictors of Venous Thromboembolism after Pulmonary Resection for Lung Cancer – an Analysis of the STS General Thoracic Surgery Database

A. L.. Axtell¹, H. Gaissert², X. Bao², H. Auchincloss², E. Walsh², D. Chang², Y. Colson³, M. Lanuti^2
1University of Wisconsin, Verona, Wisconsin ²Massachusetts General Hospital, Boston, Massachusetts ³Massachusetts General Hospital - Thoracic Surgery, Boston, Massachusetts

Purpose: Venous thromboembolism (VTE) is a major cause of morbidity and mortality in patients undergoing oncologic surgery. We sought to identify risk factors for postoperative VTE and VTE-associated mortality, to improve the safety of lung cancer resection and identify high-risk groups which may benefit from enhanced perioperative prophylactic measures.

Methods: A retrospective national cohort analysis using the Society of Thoracic Surgeon’s General Thoracic Surgery Database was conducted on 57,531 adult patients who underwent a pulmonary resection for lung cancer between January 2009 and June 2021. Patients who underwent an extrapleural pneumonectomy or emergency resection were excluded. Minimally invasive and open approaches to surgery were included. Baseline clinical, operative, and pathologic characteristics as well as postoperative outcomes were compared between patients who did and did not develop a clinically detectable postoperative pulmonary embolism (PE) or deep venous thrombosis (DVT). Multivariable regression models were developed to identify independent risk factors associated with the development of postoperative PE or DVT. Additionally in those patients who developed postoperative PE, a multivariable model was developed to identify predictors of mortality. A subgroup analysis in pneumonectomy patients further elucidated risk factors for postoperative PE in this high-risk cohort.

Results: Of 57,531 patients who underwent pulmonary resection for lung cancer, 758 (1.3%) developed a postoperative PE. Patients who developed PE were more likely to be black (12% vs 7%, p< 0.001), have interstitial fibrosis (3% vs 2%, p=0.016), and a history of prior VTE (12% vs 6%, p< 0.001.) Patients who underwent a resection for locally advanced disease as well as those who underwent bilobectomy (6% vs 4%, p< 0.001) or pneumonectomy (8% vs 5%, p< 0.001) were more likely to develop postoperative PE. There was no difference in the proportion of postoperative PE based on preoperative pulmonary function, histology, or neoadjuvant therapy. Patients with postoperative PE had increased 30-day mortality (14% vs 3%, p< 0.001), reintubation (25% vs 8%, p< 0.001), and readmission (49% vs 15%, p< 0.001.) On multivariable analysis, black race (OR 1.74 [1.39-2.16], p< 0.001), interstitial fibrosis (OR 1.77 [1.15-2.72], p=0.009), extent of resection (OR for pneumonectomy relative to wedge 1.92 [1.33-2.78], p< 0.001), and increased operative duration (OR 1.06 [1.04-1.08], p>0.001) were independently predictive of postoperative PE. A minimally invasive approach compared to thoracotomy was protective against VTE (VATS 0.89 [0.78-1.02], p=0.091; RATS 0.79 [0.67-0.92], p=0.003]. In the 758 patients who developed postoperative PE, multivariable predictors of 30-day mortality are presented in Table 1.

Conclusion: Black race, interstitial lung disease, and advanced-stage disease requiring bilobectomy or pneumonectomy are risk factors for clinically detectable postoperative PE and associated mortality; however increased symptom burden could also be associated with more diagnostic imaging. Enhanced perioperative prophylactic measures should be considered in these high-risk cohorts including lower extremity doppler-ultrasonography.

Identify the source of the funding for this research project: The data for this research were provided by The Society of Thoracic Surgeons’ National Database Participant User File Research Program. Data analysis was performed at the investigators’ institution.