Cancer is the most important acquired risk factor of thromboembolisms. More than 20% of all episodes of venous thromboembolism (VT) or pulmonary thromboembolisms (PT) are cancer related. Cancer patients with VT or PT are treated with low molecular weight heparins (LMWH) during at least 3 months, but nowadays the duration of treatment is not accurately determined.

The D-Dimer determination has been used like recurrence predictors after LMWH treatment suspension, but in cancer patients the useful is limited. Phospholipid-dependent microparticles could been used like recurrence predictors in cancer patients and tailored the duration of LMWH treatment for each patient.

We are carrying out a study in Cancer-associated-thromboembolism patients in order to decide the suitable anticoagulation time. A set of exclusion criteria is being used to determine in which patients LMWH will be withdrawn. Patients are being followed after LMWH withdrawal until 6 months. Blood samples are being taken at baseline (LMWH withdrawal), 3 weeks and 3 months after. We will look for association between several biomarkers and venous thromboembolism recurrences.

Inclusion Criteria:

• Patient with diagnosis of cancer (any) and diagnosis of pulmonary thromboembolism (PT) or venous thromboembolism (VT) , in treatment with low molecular weight heparin (LMWH).
• Patients treated with LMWH since cancer diagnostic.
• Signed informed consent sheet

Exclusion Criteria:

• Patients with life expectancy lower than 6 months
• Pregnancy woman
• Patients with cerebral metastasis

Patient with diagnosis of cancer (any) and diagnosis of pulmonary thromboembolism (PT) or venous thromboembolism (VT) , in treatment with low molecular weight heparin (LMWH).