Survival Implications of Thrombus Recurrence or Bleeding in Cancer Patients Receiving Anticoagulation for Venous Thromboembolism Treatment.

Background:  Study aims were to analyze prospectively collected data from patients with cancer-associated venous thromboembolism (VTE) to determine the impact of VTE recurrence and anticoagulant-related bleeding on all-cause mortality.

Patients/methods:  Consecutive cancer patients with acute VTE treated with anticoagulants (March 1, 2013-November 30, 2021) were included in this analysis. Anticoagulant therapy-associated VTE recurrences, major bleeding, and clinically relevant nonmajor bleeding (CRNMB) were assessed for their impact on all-cause mortality outcomes.

Results:  This study included 1,812 cancer patients with VTE. Of these, there were 97 (5.4%) with recurrent VTE, 98 (5.4%) with major, and 104 (5.7%) with CRNMB while receiving anticoagulants. Recurrent VTE (hazard ratio [HR]: 1.52; 95% confidence interval [CI]: 1.16-2.00;  = 0.0028), major bleeding (HR: 1.82; 95% CI: 1.41-2.31;  = 0.006), and CRNMB (HR; 1.38; 95% CI: 1.05-1.81;  = 0.018) each adversely influenced mortality outcomes. Deep vein thrombosis as the incident thrombotic event type was associated with VTE recurrence (HR: 1.78; 95% CI: 1.08-2.89;  = 0.02). Neither cancer type nor stage, chemotherapy, or Ottawa risk category influenced VTE recurrence. Higher body weights (HR: 1.01; 95% CI: 1.00-1.01;  = 0.005) were associated with increased major bleeding, while high Ottawa scores (HR: 0.66; 95% CI: 0.46-0.96;  = 0.03) and apixaban treatment (HR: 0.62; 95% CI: 0.45-0.84;  = 0.002) were associated with fewer major bleeding outcomes.

Conclusion:  Among cancer patients receiving anticoagulant therapy for VTE, adverse outcomes such as VTE recurrence, major bleeding, or CRNMB increase mortality risk by 40 to 80%. Identifying variables predicting these outcomes may help risk-stratify patients with poor prognosis.