A 47-year-old man was referred to our hospital because of dyspnea, cough and weight loss. On physical examination, marked dilatation of thoraco-superficial epigastric venous anastomosis was found. The chest wall collateral vessels revealed enlarged head-to-toe flow, suggesting complete obstruction of the SVC and one or more of the major caval tributaries, including the azygos system. Thoracic CT demonstrated that a huge anterior mediastinal tumor completely obstructed the superior vena cava. He was diagnosed with Hodgkin lymphoma of the nodular sclerosis type, Stage III(X)B based on the biopsy specimen from the right subcutaneous lumbodorsal mass.