**5. References**


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**4** 

*Saudi Arabia* 

**Venous Thromboembolism in Cancer Patients** 

*2Haematologist Princess Noorah Oncology Center, Head of King Abdullah International* 

Venous Thromboembolism (VTE) is a major complication of cancer and is one of the leading causes of death in patients with cancer. The risk for VTE in this group of patients is increased several folds in hospitalized cancer patient and in those on active therapy. The short and long term consequences of VTE diagnosis in cancer patients are many including increased in mortality rate, bleeding while on therapy for VTE. It has, therefore, become important to identify the risk factors for cancer-associated VTE, develop guidelines for prevention strategies for high-risk patients as well as management of VTE when it complicates the course of cancer disease or its treatment with chemotherapy immunomodulatory agents, antiangiogenesis or hormonal therapy. Proper understanding of the epidemiology and pathophysiology of VTE and its risk factors in cancer patients is central to adequate prevention and management of this serious complication in cancer

**2. The epidemiology and pathophysiology of venous thrombosis in cancer** 

The haemostatic system is a complex, multifaceted mechanism that participates in maintaining the integrity of the vascular system and fluidity of blood. In coordination with the mechanisms of inflammation and repair, the haemostatic mechanism produces a coordinated response. Haemostatic systems are normally quiescent and are only activated after injury and results in the production of a platelet plug, fibrin-based clot, deposition of

Tumor cells can activate blood coagulation through multiple mechanisms, including (a) production of procoagulant, fibrinolytic, and proaggregating activities; (b) release of proinflammatory and proangiogenic cytokines and (c) direct interaction with host vascular

Miller et al (1) studied the link between the haemostatic systems and cancer where the authors evaluated haemostatic status every year for 4 years in a population of approximately 3000 middle-aged men without cancer. Among patients with the activation

white cells at the site of injury, and activation of inflammatory and repair processes.

**2.1 Cancer cells and the haemostatic mechanisms** 

and blood cells through adhesion molecules.

**1. Introduction** 

patients.

**patients** 

*1Haematology – Faculty of Medicine, King Abdulaziz University, Jeddah,* 

*Medical Research Center, King Abdulaziz Medical City, Jeddah,* 

Galilah F. Zaher1 and Mohamed A. Abdelaal2

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