Recurrent venous thromboembolism in glioblastoma.

BACKGROUND: Patients with glioblastoma (GBM) are at increased risk of initial and recurrent venous thromboembolism (VTE) but rates of recurrence and real-world treatment choices are incompletely understood.

OBJECTIVES: We aim to describe the treatment of incident VTE, report incidence and risk factors for recurrence.

PATIENTS/METHODS: We conducted a retrospective cohort study of consecutive Cleveland Clinic patients with GBM presenting with objectively diagnosed deep vein thrombosis (DVT) or pulmonary embolism (PE) from 2007 to 2013 with at least 6-month follow-up. We collected information on patient demographics, VTE incidence, treatment and recurrence. Data were analyzed using multivariate logistic regression analysis.

RESULTS: Of 450 patients with GBM, 145 (32.2%) developed VTE and comprised the study population. Of these, 11 (7.6%) experienced PE, 117 (80.7%) had DVT and 16 (11%) had DVT as well as PE. Fifty five (37.9%) VTE events occurred in the first 30 post-operative days and 56 (38.6%) during chemotherapy. Thirty one (21.4%) patients were untreated. Treatments included enoxaparin (N=36, 24.8%), warfarin (15, 10.3%) or vena cava filters either alone (N=39, 26.9%) or in combination with anticoagulation (N=21, 14.5%). Recurrent VTE occurred in 39 patients (26.9%).In multivariate analysis, lack of long term anticoagulation (HR 11.2, CI 1.5-86.3, p<0.05) and the presence of second primary malignancy (HR 3.69, CI 1.2-11.1, p<0.05) were significantly associated with recurrent VTE.

CONCLUSION: VTE and recurrent VTE are highly prevalent throughout the disease course among patients with GBM. Long term anticoagulation is associated with reduced risk of recurrent VTE but is often not utilized.