RESUMO
Superior vena cava thrombosis (SVCT) is a rare pathology, though of great significance since it implies the development of a malignant process. The most common etiologies are basically bronchopulmonary and mediastinal tumors. Observations involving 2 patients presenting with superior vena cava syndrome (SVCS) are reported in this study, in which radiologic investigations (chest roentgenogram, computed tomography scan of the thorax, and superior vena cavography) revealed thrombosis of the SVC disclosing in both cases a non-Hodgkin's lymphoma. The first case was a mediastinal Burkitt's lymphoma in a thirty-eight-year-old man (exceptional form) and in the second case a lymphoblastic non-Hodgkin's lymphoma in a nine-year-old girl. In the patient with Burkitt's lymphoma healing was satisfactory twenty-four months after treatment by surgery, chemotherapy, and radiotherapy. The second patient died suddenly. In both cases the SVCT revealed the tumor. The causes of SVCT are reviewed and discussed.