VIII Preface very rich in publications on the subject, epidemiology, etiology, pathogenesis, risk stratification, VTE in different groups of medical and surgical conditions, diagnosis, management, guidelines for thromboprophylaxis and management. As it is not possible to have a comprehensive book that covers all aspects of VTE, in this book we have elected to address certain etiological aspects of venous thrombosis: VTE in neonates, children, chronic renal disease and VTE in cancer patient with special reference to anti-cancer agents associated with high risk of VTE, especially in tertiary care settings.Several national and international registries have helped to define the epidemiology, risk factors for VTE in different age groups and demonstrated the important differences between VTE in adults and pediatric patients and called for evidencebased guidelines for management and prevention of VTE in neonates and children. In chapter 3, Dr. Lazaro and colleagues described the magnitude of this problem including diagnosis and management.The same authors also gave a detailed account of VTE in patients with chronic renal disease, with special reference to epidemiology, pathogenesis, and treatment in this important group of patients with a special reference to unfractionated heparin, low molecular heparin, the pentasaccharide and some of the novel oral anticoagulants.Although cancer has been clearly associated with venous thromboembolism, many aspects of this relation are still not well understood, including the cancer sites most associated with VTE and the risk for cancer development during follow-up of patients with idiopathic VTE. In chapter 4, the authors have depicted an informative updated account on the epidemiology, pathogenesis, patient-related factors, cancer-related factors and treatment related factors and their impact on the risk of VTE in cancer patients with special emphasis on some chemotherapeutic agents associated with VTE. The authors also put up some practical information on thromboprophylaxis in cancer patients at different clinical settings.The use of immunomodulatory agents thalidomide and, lately, its second generation Lenalidomide, has revolutionized the management of multiple myeloma patients. However, their use carries a significant risk of thrombosis. Dr. Mateos and Dr. Gonzalez-Porras, chapter 5, assembled an excellent account on those agents in a practical format, which helps the practicing oncologists and hematologists in handling those effective agents to minimize the risk of the VTE associated with the use of those agents.Dr. Agutter and Dr. Malone from Theoretical Medicine and Biology Group, UK, argued elegantly for a rational approach for mechanical thromboprophylaxis in chapter 6. The authors summarized the valve cusp hypoxia hypothesis, discussed its clinical implications and suggested a sound approach to prophylaxis based on this hypothesis.