The textbook is used for classroom studies and independent work of students in the study of prevention and treatment of venous thromboembolic complications in patients with malignant tumors. The content covers the main issues of determining the risk of venous thromboembolic complications and methods of their prevention and treatment in patients with locally advanced and metastatic malignant tumors. The textbook is intended for students in higher education (graduate students, residents, interns, students) and in additional professional education (students of advanced training cycles). The textbook was approved as educating manual by the Scientific Council of NMRC of Oncology n.a. N.N. Petrov HM of RF (protocol №10 from 09.27.2016).