Real-World Use and Outcomes of Post-Discharge Venous Thromboembolism Prophylaxis After Thoracic Cancer Operation

BACKGROUND: Post-discharge venous thromboembolism prophylaxis is conditionally recommended after thoracic cancer operation, but real-world use and associated outcomes across procedures and operative approaches remain poorly characterized. STUDY DESIGN: We conducted a retrospective Epic Cosmos cohort study of adults undergoing lung or esophageal cancer resection from 2016-2025. Post-discharge prophylaxis was defined as prophylactic-dose anticoagulation prescribed within 7 days of discharge. Thirty-day outcomes were compared using 1:3 propensity-score matching stratified by procedure and operative approach. RESULTS: Among 157,619 patients (14,277 esophagectomy; 143,342 lung resection), 11.15% and 1.48%, respectively, received post-discharge prophylaxis. After open esophagectomy, prophylaxis was associated with lower DVT (1.23% vs 2.63%; p=0.039), PE (0.46% vs 1.44%; p=0.047), and mortality (1.70% vs 5.20%; p<0.001), without significantly increased bleeding. Findings were similar after minimally invasive esophagectomy: DVT 0.32% vs 1.46% (p=0.003), PE 0.21% vs 0.89% (p=0.034), and mortality 1.28% vs 3.20% (p=0.003). After open lung resection, prophylaxis was associated with lower PE and mortality but higher bleeding and healthcare use. After minimally invasive lung resection, thromboembolic outcomes did not significantly differ, while bleeding and healthcare use were higher. Enoxaparin accounted for 79.35% of prophylaxis prescriptions; thromboembolic outcomes did not significantly differ between apixaban and enoxaparin. CONCLUSIONS: Associations between post-discharge thromboprophylaxis and outcomes differed across thoracic procedures and operative approaches. Favorable associations after esophagectomy contrasted with less consistent lung resection findings, supporting prospective studies to define procedure- and risk-specific prophylaxis strategies.