Anticoagulant prescribing patterns in patients with primary central nervous system malignancies and secondary metastases

Abstract

To evaluate the safety of direct oral anticoagulants (DOACs) versus low-molecular weight heparin (LMWH) in patients with central nervous system (CNS) malignancies and secondary metastases. All adult patients with CNS malignancies and secondary metastases who were treated with a DOAC or LMWH for any indication from 2018 to 2022 were included. The primary outcome was the incidence of any intracranial hemorrhage (ICH) after anticoagulation initiation. Secondary outcomes included non-ICH bleeding events and thromboembolic events. Tolerability was assessed by any changes in anticoagulant therapy during study period. 153 patients were included; 48 patients received enoxaparin and 105 received DOACs, of which apixaban was used most commonly. The population was predominantly White (74%) and male (59%) with a median age of 65. Data was censored for immortal time bias for outcomes evaluated beyond 3 months. ICH occurred in 7.7% of the population, more frequently in the enoxaparin group (DOACs 4, 4% vs. enoxaparin 7, 16%, p = 0.037). Non-ICH bleeds were predominantly minor and more common in the DOAC group (DOACs 13, 13% vs. enoxaparin 1, 2%, p = 0.037). Thromboembolic events were not different between groups (DOACs 9. 9% vs, enoxaparin 2, 4%, p = 0.503). Anticoagulant switches occurred more in the enoxaparin group (DOACs 12, 12.4% vs. enoxaparin, 37.8%, p < 0.001), primarily due to patient or provider preference. Our data supports DOACs to be preferred over LMWH for the treatment of VTE or for stroke prevention with AF to prevent ICH in patients with brain tumors or metastases.

Keywords: Anticoagulant; Brain metastases; CNS malignancy; DOAC; Direct oral anticoagulant; LMWH; Low-molecular-weight-heparin.