Anticoagulation management and outcomes in patients with cancer-associated small venous thromboembolism: a retrospective cohort study

Background: The anticoagulant management and outcomes in patients with cancer and distal lower extremity deep vein thrombosis (dDVT) or subsegmental pulmonary embolism (SSPE) remain unclear. Objectives: The objective of this study was to assess the anticoagulation management strategies for dDVT and/or SSPE in patients with cancer and their associated outcomes. Methods: We conducted a single-center retrospective cohort study in patients ≥18 years old with active cancer and dDVT and/or SSPE. Patients were followed for 12 months or until death. The primary efficacy outcome was recurrent venous thromboembolism (VTE) at 6 months, and the primary safety outcome was major bleeding. We calculated the cumulative incidence of outcomes with 95% CI, considering death as a competing risk. Results: We identified 149 patients with isolated dDVT and 119 with SSPE ± dDVT. Anticoagulation was initiated in 85% of patients, most often with therapeutic doses. The 6-month cumulative incidences of recurrent VTE in the dDVT and SSPE cohorts were 17.9% (95% CI, 12.1-24.6) and 7.1% (95% CI, 3.3-12.9), respectively. The 6-month cumulative incidences of major bleeding were 7.9% (95% CI, 4.0-13.5) and 5.5% (95% CI, 2.2-10.9), respectively. Exploratory analysis stratified by the use of anticoagulation showed that patients not initiated on anticoagulation had a numerically higher incidence of recurrent VTE in the dDVT group. Conclusion: Patients with cancer-associated dDVT and/or SSPE had a substantial risk of recurrent VTE, especially in those not on anticoagulation.