[Acute venous thrombosis as the first symptom of malignant diseases (author's transl)].

Up to this time, malignant diseases not clinically manifest have repeatedly been found as causes of acute venous thromboses. Among our own patients this occurred in 5 cases out of 35 acute venous thromboses in 3 years. Since the indication for venous thrombectomy is greatly restricted by the presence of a malignant disease as the cause of this thrombosis, exclusion of a tumor must be aimed at before indication for thrombectomy is made. Very rare intravascular tumors of the vessel require careful histological investigation of every thrombus removed.