Direct oral anticoagulant therapy for cancer-associated venous thromboembolism in routine clinical practice

Abstract

Background: The efficacy and bleeding complications of direct oral anticoagulant (DOAC) therapy for cancer-associated venous thromboembolism (VTE) in routine clinical practice remain unclear. Moreover, data on long-term outcomes in patients with cancer-associated VTE who received DOAC therapy are limited. Methods and Results: This retrospective study enrolled 1,096 consecutive patients with acute VTE who received warfarin or DOAC therapy between April 2014 and May 2017. The mean follow-up period was 665±490 days. The number of cancer-associated VTE patients who received DOAC therapy was 334. Patients who could not be followed up and those prescribed off-label under-dose DOAC were excluded. Finally, 303 patients with cancer-associated VTE were evaluated. The number of cases of major bleeding and VTE recurrence was 54 (17.8%) and 26 (8.6%), respectively. In the multivariate analysis, the factors correlated with major bleeding were high cancer stage, high performance status, liver dysfunction, diabetes mellitus, and stomach cancer; those correlated with recurrent VTE were initial diagnosis of pulmonary embolism, uterine cancer, and previous cerebral infarction. Major bleeding was an independent risk factor of all-cause death. In the Kaplan-Meier analysis, those who received prolonged DOAC therapy had lower composite major bleeding and recurrent VTE risks than those who did not. Conclusions: In DOAC therapy for cancer-associated VTE, major bleeding prevention is important because it is an independent risk factor of death.