Venous thromboembolism (VTE) is an increasingly common cause of morbidity and mortality in cancer patients. In various malignancies the incidence of thrombosis ranges from 5% to 60%, that is four times higher in cancer patients compared to the general population. Large retrospective studies have shown that in men the tumors which are most commonly associated with VTE are lung cancer and pancreatic cancer and, in women cancer of the genital area, pancreas, colon and rectum. Thromboembolic events may often occur before the cancer diagnosis. We present the case of a 41-year-old female patient with a history of genital cancer which was surgically treated and who is now admitted for clinical signs of ileofemoral deep vein thrombosis (DVT) of the left leg. The diagnosis was confirmed by laboratory data and Doppler ultrasound and the patient received anticoagulant treatment. Given the history of the patient, abdominal and pelvic ultrasound and computer tomography (CT) were performed to detect the cause who predisposed to the thrombotic event. These confirmed the ovarian cancer, this time on the right side, and the presence of hepatic and pulmonary metastasis. This case highlights the importance of screening for a cause of the thromboembolic event in patients, especially in those who have a history of a neoplasia.