Current management of cancer-associated venous thromboembolism in patients with thrombocytopenia: a retrospective cohort study

Optimal management of venous thromboembolism (VTE) in cancer patients with thrombocytopenia is uncertain. We described current management and clinical outcomes of these patients. We retrospectively included a cohort of cancer patients with acute VTE and concomitant mild (platelet count 100,000-150,000/mm(3)), moderate (50,000-99,000/mm(3)), or severe thrombocytopenia (< 50,000/mm(3)). Univariate and multivariate logistic regression analyses explored the association between different therapeutic strategies and thrombocytopenia. The incidence of VTE and bleeding complications was collected at a 3-month follow-up. A total of 194 patients of whom 122 (62.89%) had mild, 51 (26.29%) moderate, and 22 (11.34%) severe thrombocytopenia were involved. At VTE diagnosis, a full therapeutic dose of LMWH was administered in 79.3, 62.8 and 4.6% of patients, respectively. Moderate (OR 0.30; 95% CI 0.12-0.75), severe thrombocytopenia (OR 0.01; 95% CI 0.00-0.08), and the presence of cerebral metastasis (OR 0.06; 95% CI 0.01-0.30) were independently associated with the prescription of subtherapeutic LMWH doses. Symptomatic VTE (OR 4.46; 95% CI 1.85-10.80) and pulmonary embolism (OR 2.76; 95% CI 1.09-6.94) were associated with the prescription of full therapeutic LMWH doses. Three-month incidence of VTE was 3.9% (95% CI 1.3-10.1), 8.5% (95% CI 2.8-21.3), 0% (95% CI 0.0-20.0) in patients with mild, moderate, and severe thrombocytopenia, respectively. The corresponding values for major bleeding and mortality were 1.9% (95% CI 0.3-7.4), 6.4% (95% CI 1.7-18.6), 0% (95% CI 0.0-20.0) and 9.6% (95% CI 5.0-17.4), 48.2% (95% CI 16.1-42.9), 20% (95% CI 6.6-44.3). In the absence of sound evidence, anticoagulation strategy of VTE in cancer patients with thrombocytopenia was tailored on an individual basis, taking into account not only the platelet count but also VTE presentation and the presence of cerebral metastasis.