Predictors of the Indefinite-Duration Anticoagulation Treatment Strategy In Patients with Cancer-Associated Thrombosis.

In patients with cancer and acute venous thromboembolism (VTE), current consensus guidelines recommend anticoagulation therapy for an indefinite duration or until the cancer is resolved.

Among 1’247 patients with acute VTE enrolled in the Swiss Venous Thromboembolism Registry (SWIVTER) from 18 hospitals, 315 (25%) had cancer of whom 179 (57%) had metastatic disease, 159 (50%) ongoing or recent chemotherapy, and 83 (26%) tumor surgery within 6 months. Patients with cancer were older (66±14 vs. 60±19 years, p<0.001), more often hospitalized at the time of VTE diagnosis (46% vs. 36%, p=0.001), immobile for >3 days (25% vs. 16%, p<0.001), and more often had thrombocytopenia (6% vs. 1%, p<0.001) than patients without cancer. The 30-day rate of VTE-related death or recurrent VTE was 9% in cancer patients vs. 4% in patients without cancer (p<0.001), and the rates of bleeding requiring medical attention were 5% in both groups (p=0.57). Cancer patients received indefinite-duration anticoagulation treatment more often than patients without cancer (47% vs. 19%, p<0.001), and LMWH mono-therapy during the initial 3 months was prescribed to 45% vs. 8%, p<0.001, respectively. Among patients with cancer, prior VTE (OR 4.0, 95%CI 2.0–8.0), metastatic disease (OR 3.0, 95%CI 1.7–5.2), outpatient status at the time of VTE diagnosis (OR 3.8, 95%CI 1.9–7.6), and inpatient treatment (OR 4.4, 95%CI 2.1–9.2) were independently associated with the prescription of indefinite-duration anticoagulation treatment.

Less than half of the cancer patients with acute VTE received a prescription for indefinite-duration anticoagulation treatment. Recurrent VTE, metastatic cancer, outpatient VTE diagnosis, and VTE requiring hospitalization were associated with an increased use of this strategy.

Spirk:sanofi-aventis (suisse) sa: Employment.